Keyword strategy for blog posts: Primary, Secondary & LSI

Keyword strategy for blog posts: balancing primary, secondary, and semantic keywords

I still remember the first time I tried to strictly follow an ‘LSI keyword’ list. I had a primary keyword, a handful of secondary terms, and then a list of about 40 “related” phrases generated by a tool. I pasted them all into a document and tried to weave them into the narrative. The result? A blog post that read like a robot having a stroke. The headings were awkward, the sentences felt forced, and I realized I had completely lost the plot.

That was a pivotal moment for me. I realized that trying to score 100% on a tool’s optimization checklist often meant scoring 0% with actual human readers. Over time, I developed a sanity-check approach: a reliable framework that balances SEO requirements with the need to sound like a sane human being.

In this guide, I’m going to walk you through the exact keyword strategy for blog posts I use today. This isn’t about stuffing synonyms into white text; it’s about understanding search intent, mapping keywords to a logical structure, and knowing when to stop optimizing and start publishing.

Search intent: informational (guide + framework + checklist)

This article is an actionable guide designed for intermediate content marketers and SEOs. You will find a clear workflow, a decision-making framework for keyword selection, and a maintenance plan to keep your content performing over time.

Quick takeaway (optional): the balance in one sentence

The winning formula: Use your primary keyword to anchor the topic, secondary keywords to define your H2 subtopics, and semantically related terms to prove topical depth—without ever sacrificing readability for a score.

LSI keywords vs. semantic SEO: what actually matters today (and why the myth won’t die)

If you have heard that you need to use ‘LSI keywords’ to rank, you are not alone. It is advice that persists in older blog posts and legacy tool interfaces. However, from a technical standpoint, LSI (Latent Semantic Indexing) is effectively a zombie concept in modern SEO.

The Reality Check:

• The Myth: Google uses LSI to match exact synonyms in your text to search queries.
• The Fact: Google’s John Mueller has explicitly stated that “there’s no such thing as LSI keywords” for SEO purposes .
• The Shift: Google has moved to semantic SEO, which relies on entities (concepts, people, places) and the relationships between them, not just matching text strings.

LSI is a technology developed in the late 1980s for small, static databases. It simply isn’t scalable or sophisticated enough for the modern web. So, why does the term stick around? Because it’s a convenient shorthand for “words related to my topic.” But using the wrong mental model leads to the wrong strategy.

What people mean when they say ‘LSI keywords’

Usually, when a client or a tool tells you to add LSI keywords, they are actually asking for topical depth. They want you to include related subtopics, synonyms, and variations that a comprehensive article on the subject would naturally contain. Think of it less like a “word list” and more like a “topic map.”

What semantic SEO is (in plain English)

Semantic SEO is about meaning and context. Modern algorithms like BERT and MUM allow search engines to understand that a search for “apple” in the context of “pie” refers to a fruit, while in the context of “iPhone” it refers to a brand. To win here, you don’t need to repeat the word “fruit” 10 times; you need to mention attributes like “peel,” “core,” “recipes,” and “varieties.” This signals to Google that you aren’t just keyword stuffing—you are covering the entity completely.

How I build a keyword strategy for blog posts: primary keyword, secondary keywords, and semantic coverage

To keep my outlines clean, I categorize every term I find into one of three buckets. Each bucket has a specific job to do on the page. If you try to make a secondary keyword do a primary keyword’s job, you end up with a confused article that doesn’t know what it’s about.

For example, if I’m writing about “employee onboarding,” my strategy looks like this:

Primary keyword: the page’s ‘promise’ to the searcher

This is the anchor. I choose one primary keyword per page. Just one. This term dictates the URL, the H1 title, and the core intent of the article. If I can’t summarize the purpose of the page in one sentence using this keyword, it’s probably too broad.

• Example: “Employee onboarding checklist”

Secondary keywords: the subtopics that earn relevance (without creating thin pages)

These are the variations and sub-questions that define your H2 and H3 headings. They help you capture long-tail traffic without needing to write a separate, thin 500-word post for every single variation.

My decision rule: If a secondary keyword is distinct enough to require 300+ words of unique advice, I split it into a new post. If it shares 80% of the same answer as the primary, I keep it here as a subheading.

• Example: “New hire paperwork,” “remote onboarding steps,” “onboarding timeline.”

Semantic terms (not ‘LSI’): entities, attributes, and related concepts

These are the words that naturally appear when an expert discusses the topic. They are the glue. You don’t force them into headings; you sprinkle them into paragraphs to provide context. They signal to Google that your content is authoritative.

• Example: “HRIS,” “direct deposit,” “company culture,” “mentorship,” “probation period.”

Table: primary vs secondary vs semantic terms (what to use, where, and why)

Keyword Type	Primary Role	Best Placement	Target Frequency	Common Mistake
Primary Keyword	Define the main topic	URL, Title Tag, H1, Intro, Conclusion	Focus on placement, not count	Targeting 2-3 different topics in one post
Secondary Keywords	Define sub-sections (H2/H3)	H2s, H3s, FAQ section	Once per relevant section	Creating separate, thin posts for close variants
Semantic Terms	Provide context & proof of depth	Body paragraphs, lists, alt text	Natural distribution	Forcing synonyms where they don’t fit

My step-by-step workflow to create a keyword strategy for blog posts (from idea to outline)

This is the exact process I use. It moves from the user’s needs to the technical execution. I find that if I skip the first step, I usually end up having to rewrite the draft later.

Step 1: confirm the job-to-be-done (intent) before you pick keywords

Before I open any tool, I ask: What is the user trying to achieve? A small business owner searching for “employee onboarding” might want a conceptual definition, but if they search for “employee onboarding checklist,” they have a specific job: they need a list of tasks to not get sued or look unprofessional. I align my content with that job.

Step 2: pick one primary keyword and define the ‘one-sentence promise’

I choose the highest-volume keyword that accurately matches that intent. Then I write my H1 promise.

• Vague promise: “All about onboarding.”
• Clear promise: “A complete employee onboarding checklist for US small businesses.”

Step 3: scan the SERP to see what Google is rewarding

I spend 3 minutes scanning the live results for my primary keyword. I’m not looking for copy to steal; I’m looking for patterns .

• Are the top results listicles, how-to guides, or software landing pages?
• What questions appear in the ‘People Also Ask’ box?
• Is there a Featured Snippet defining a specific term?

Sanity check: If the SERP is filled with free PDF templates and I’m writing a 3,000-word philosophical essay, I’m going to lose.

Step 4: collect secondary keywords and group them by sub-intent

I grab the relevant keywords from my research tool and cluster them. If I have “remote onboarding” and “virtual onboarding,” those are the same cluster. I’ll pick one for the H2 and use the other in the text.

Step 5: build semantic coverage (entities + attributes) so the post feels ‘complete’

I brainstorm the vocabulary of the topic. If I’m writing about “coffee makers,” my semantic list includes grind size, water temperature, brewing time, filter, carafe, and descaling. I don’t need a tool to tell me this; common sense and subject matter expertise are often your best SEO tools.

Step 6: map keywords to the outline (H2/H3) before drafting

I never write without a skeleton. I map my secondary keywords to H2s. I often try to write the H2s as questions first—it forces me to be helpful.

• H2: What paperwork is required? (Target: “new hire forms”)
• H2: How to handle the first week? (Target: “onboarding timeline”)

Step 7: draft fast, then optimize (don’t optimize line-by-line as you write)

When I’m drafting, I turn the SEO part of my brain off. I focus on clarity and flow. If I stop to check if I’ve used the word “paradigm” enough times, the writing suffers. I only check against my keyword list during the editing phase. For those looking to speed up this specific part of the process, using a workflow that incorporates an AI article generator can help get the initial structure down, but the human editorial review is where the semantic magic happens.

On-page execution: where keywords belong (titles, headings, body, links, and schema)

Once the draft is written, I do an “optimization pass.” This is where I ensure the robot understands what the human just read.

Title tag + H1: match the promise, not a keyword list

Your Title Tag is for the search engine results page (SERP); your H1 is for the user who clicked. They should be similar but don’t have to be identical. I always place the primary keyword as close to the beginning of the title tag as possible, provided it sounds natural.

Formula: [Primary Keyword] + [Benefit/Hook] | [Brand Name]

H2/H3 structure: use secondary keywords as sections only when they earn a paragraph

I ask myself: Does this keyword deserve its own headline? If adding the keyword “best onboarding software” forces me to write a weird, disjointed paragraph just to include it, I cut it or move it to a list item. Headings must guide the reader’s eye, not just the crawler.

Internal links + anchor text: descriptive, not repetitive

Internal links connect your content clusters. Instead of “click here,” I use descriptive anchors. But I’m careful not to over-optimize. If I link to a page about “payroll software” 10 times, I vary the anchor text: “payroll tools,” “automating payments,” or “paying employees.”

Schema and snippets: only use what matches the content

A common misconception is that adding FAQ schema guarantees you more space on Google. It doesn’t, but it helps. I only add FAQ schema if the page actually has a Q&A section, and HowTo schema if there is a step-by-step process. Don’t try to trick the system by marking up a standard blog post as a recipe.

Business-focused example + templates (so you can copy the process)

Let’s apply this to a real B2B topic. Suppose I’m a marketing manager for a SaaS company.

Example: turn one business topic into a keyword map

• Topic: Cash Flow Forecasting
• Primary Keyword: “cash flow forecasting software” (Intent: Commercial/Investigation)
• Secondary Keywords (H2s):
  • “benefits of automated forecasting”
  • “cash flow forecasting methods” (Direct, Indirect)
  • “excel vs software for cash flow”
• Semantic Terms (Body): liquidity, runway, accounts receivable, balance sheet, variance analysis, burn rate.

I’m not trying to rank for “what is money”—that’s too broad. I’m focusing on the specific job of forecasting.

Table template: keyword → intent → page section → evidence (SERP/PAAs)

You can copy this simple table into your own content briefs. I fill this out in about 15 minutes max.

Keyword / Cluster	User Intent	Proposed Section	SERP Notes (Format to match)
[Primary Keyword]	[Learn / Do / Buy]	H1 & Intro	Identify if SERP is guides or tools
[Secondary 1]	[Sub-topic Intent]	H2 Heading	Check PAA questions
[Secondary 2]	[Comparison]	H2 or Table	Is there a feature snippet?
[Semantic List]	Context	Body Copy	N/A (Natural usage)

Common mistakes when balancing keywords (and the fixes I use)

Even with a plan, it’s easy to mess up. Here are the most common “optimization” errors I see in drafts and how I fix them.

1. Mistake: Treating ‘LSI’ like a checklist. Forcing phrases like “best cash flow tool free online” into a sentence just because a tool said so.
   
   Fix: Ignore grammatical nightmares. Focus on the entity (e.g., “free tools”).
2. Mistake: Stuffing keywords into H2s.
   
   Bad H2: Why Cash Flow Forecasting Software is Important for Cash Flow Forecasting.
   
   Better H2: Why automating your forecast saves time.
   
   Insight: Updating H2s to be more semantically relevant (and less spammy) has been shown to increase organic CTR significantly .
3. Mistake: Optimizing for multiple primary keywords. Trying to rank for “accounting software” and “bookkeeping tips” in one post.
   
   Fix: Pick one lane. If the intents are different, split the posts.
4. Mistake: Ignoring internal links. Publishing a “content island” that no other page links to.
   
   Fix: I have a rule: I cannot publish a post until I have found at least 3 older posts on my site to link from.

Maintenance plan: when to refresh keywords, headings, and performance (plus quick FAQs)

SEO isn’t a “set it and forget it” channel. Competitors publish new content, and search intent shifts. Here is the refresh schedule I recommend to keep your strategy alive:

Refresh cadence checklist (simple calendar)

• Every 1-2 Months (On-Page Tweak): Check your CTR. If impressions are high but clicks are low, re-write the Title Tag and H1. Tweak H2s to better match current PAA questions.
• Every 3-6 Months (Research Refresh): Re-run the primary keyword in your tool. Have new competitors appeared? Are there new secondary keywords you missed? Add a new section if needed.
• Quarterly (Technical Audit): Scan for broken links and update outdated stats.

For those managing this at scale, using an SEO content generator, an AI content writer, or a specialized AI SEO tool can help automate the detection of these decay signals and streamline the updating process.

FAQ: Are LSI keywords still relevant for SEO today?

Technically, no. Google does not use LSI (old 1980s tech). However, the concept of covering “related topics” and “semantically relevant entities” is critical. Focus on meaning and context, not the specific LSI label.

FAQ: How should I balance primary, secondary, and semantically related keywords in a blog post?

Use the Anchor + Support model. The primary keyword anchors the page title and URL. Secondary keywords support the structure as H2/H3 headings. Semantic terms support the body content to prove expertise. A good rule of thumb: If reading a sentence out loud feels awkward, you have over-optimized.

FAQ: How often should I refresh my content for optimal SEO performance?

Small updates beat rare overhauls. I recommend a light review every 3 months. Even updating the publication date (after making genuine improvements to the content) can signal freshness to Google.

FAQ: What immediate changes can boost SEO engagement?

If you need a quick win, look at your H2s. Rewrite generic headings (e.g., “Conclusion” or “Tips”) to include specific benefits or semantic terms. Add a concise FAQ section at the bottom of the post targeting “People Also Ask” questions.

Conclusion: what I’d do next (recap + next actions)

Building a keyword strategy doesn’t have to be a dark art. It’s mostly about organization and empathy for the user.

Recap:

• Ditch the LSI lists; focus on entities and sub-topics.
• One page = one primary intent.
• Map keywords to headers before you write.

Your next 3 moves:

1. Open your most important existing blog post.
2. Scan the H2s: do they include relevant secondary keywords, or are they generic?
3. If they are generic, rewrite them today to be more descriptive.

If I had one hour right now, that is exactly where I would start. It’s the highest-leverage minute you can spend on your site today.