Start with your customers' words
Open your inbox, call notes and reviews. Highlight phrases customers use when they describe a need. They rarely use your trade vocabulary. A homeowner may say my sink is backing up, while you would say drain obstruction.
List twenty to thirty phrases. These are your seed terms.
Expand with free sources
Type each seed term into Google and note the autocomplete suggestions and the People also ask box. Scroll to related searches at the bottom of the results. Each gives you a variation to consider.
Your Search Console report, if you have one, lists the queries that already show your site. Some of them will surprise you.
Free keyword tools show estimated volumes, which are rough and often rounded. Use them to compare terms, not to predict exact traffic. A term with small volume but clear buying intent may be worth more than a popular term with vague intent.
Be wary of volumes for very local terms, which are often underreported.
Look at who ranks
For each promising term, search it and view the first page. Are the results service pages, directories, articles, or videos? That tells you what Google believes people want. If directories fill the page, a service page of yours may struggle, and a different term may be easier.
Note which competitors appear again and again, and read their pages for topics you have missed.
Sort into a plan
Make a table with four columns: the term, the intent, the page that should serve it, and the status. Assign one main phrase to each page, and a few related phrases that fit naturally. Do not create separate pages for near-identical phrases.
Plan new pages only where you have something real to say. The goal is a map of your site, not a list of words to repeat.
Language shifts and seasons change. Recheck your list in spring and autumn and add new terms from customer questions.
A small example table
Say you run a mobile dog grooming service. Your seed terms from customer messages might be: groomer who comes to my house, nail trim for anxious dog, how often should I groom a doodle. The first is transactional, the second is a mix of service and advice, and the third is informational.
Your plan could assign the first to your home page and service page, the second to a page about gentle handling, and the third to an article. Each has a purpose and a place on the site.
Notice that none of these needs a specific place name in the page title to work. Google understands location from many signals, and your profile, address and service area page help with that.
Avoid these research traps
Do not chase terms that attract the wrong audience, such as job seekers or do-it-yourself readers if you sell services. Do not assume a high volume means high value. And do not forget that the people who matter most are already calling you: their words, recorded in your notes, are the research that no tool can match. Revisit them each quarter.
Common questions
Do I need paid keyword tools?
Not to begin. Free tools, autocomplete and your own Search Console data are enough for a small site.
How many keywords should one page target?
One main topic with a few closely related phrases. Trying to cover many unrelated terms on a single page weakens it.
This guide is general information. Search engines change how they work and their guidelines; check Google's current documentation for your situation. Nobody can guarantee a ranking.