Not overusing keywords
The first process is looking for relevant keywords. All of your most important pages should revolve around one key concept. However, the goal of this exercise isn't to make as many instances of the term or its variations as feasible. Choosing a focus keyword for each page can help you zero in on the page's main topic of discussion. Incorporate the keyword naturally where it has to be used, and then forget about it.
Concentration of Keywords
One reason why keyword stuffing is still widely used is the idea of what constitutes an optimal keyword density, or the number of times a term or phrase "should occur" on a page. Overuse of a keyword isn't a ranking factor (and probably never was). Many SEO specialists agree that it is not anything you need worry about.
Even while receiving a green point on this part could make you feel better about yourself, it will have no effect on your ability to rank. To put it simply, it prevents you from abusing the same terms over and over again and aids in keeping your word count below reasonable limits. Ignoring the situation won't put you in harm's way.
Instead of focusing on the sheer volume of terms, you may better dissect a topic and reveal its inner workings. Truth be told, if you write extensively on a topic, you will naturally work in your focus keywords. It's pointless to insist on pursuing this matter further. Google cares more about whether or not the website provides a high-quality answer to the query and whether or not it matches the search intent. Put simply, write the best piece of content you can.
Act in an authentic manner
Last but not least, you should never force your chosen keyword or any other phrase into your website's content. How many times can you ask "what is Google Adsense" in a 2,000 word article before it seems like you have no idea what you're talking about? The emphasis should be on crafting the best possible piece of writing, not on cramming as many relevant keywords as possible into it.