Keyword research is an activity you undertake every now and then. If you have a clear definition about the product or service you want to ‘sell’ with your website, you should be able to come up with keywords, related keywords and even more related keywords to make your awesome website (more) findable. As your product and the market will evolve, your keyword strategy should do the same.
The keywords you want to focus your SEO on, should closely resemble the vocabulary of your audience. In order to come up with the proper keywords you really have to get inside the heads of the people who search for your website. What terms will people use? How do people search? Which question does your website answer? You should create a list of all search terms people could use and think of combinations and nuances within these search terms.
The simplest KW research tool is google. Type in your topic and scroll to the bottom to see what related results show up. Use those to either write an article or to supplement other articles with some of the keywords. Yes, they are primary phrases so you may not rank for them right away but building your site with these in it will help get rank for them eventually. Also look at what other articles that show up for the keyword use.
If you are using Google Adwords Keyword Planner to find new and related keywords, ignore the search volume data! The search volume data in the planner is really only useful for keywords that you’re actually spending money to advertise on. Otherwise, these volumes are not reliable. While not really helpful to decide which keyword is most used by your potential audience, Google Adwords Keyword Planner makes a useful tool in coming up with ideas for potential keywords!
These keyword research tools should make it easier to create a list of relevant search terms. You should make sure to create awesome landing pages for keywords you want to be found on. You should also think about creating engaging content articles and a great internal linking structure in order to make your SEO strategy complete.