The first step is to figure out what your target customers are searching on Google. Google Suggest is a free tool that you can use by typing in your product or service and seeing what people are searching. Another way to figure out relevant search terms is by looking at Google's “searches related to” at the bottom of the search page for your keyword. You can also use SimilarWeb or SEMrush, competitor analysis tools that tell you what your competitors are trying to rank for on Google.