You now have a total overview of potential search terms. Make a selection. Keep in mind that a low search volume is not a bad thing if the term is highly relevant to your niche!

Have you found relevant search terms that you really can't get rid of in your text, for example because they are misspelled or because you have to choose between variants such as synonyms? You can make a separate list of terms suitable for the website's internal search function. 

Then you have to start incorporating the chosen terms into your content. How to do that is explained in the Method section.