One common mistake of writers with new SEO tools is overworking SEO for a website. Keep it simple for success in the search engines. Content on your website should be related to your website's overall theme, written in straightforward language that is easy for readers to follow.
Keyword density practices are highly debatable. The range agreed upon by many SEO experts is between 2 to 20%. Anything above 20% is usually considered overuse of keywords and is not an effective strategy for SEO success. If your website is caught using keywords illogically (most search engines can detect it), you may be banned for using keywords unnaturally. Overstuffing content with keywords will look unnatural to readers as well. Make your keyword usage proportionate with the size of your content, and use a keyword density tool to confirm that you're not using a particular keyword excessively. Easy does it.