Hands down I’d say the best thing you can do is research 1 primary keyword, craft an enticing article title that includes your keyword (though it doesn’t have to be an exact match), spend time writing your search engine snippets (SEO titles/meta descriptions), and by far the most important is making your content as VALUABLE as possible through videos, nice graphics, table of contents, bold/colors/styling, etc. Small things like keyword density barely matter.
Cafe Press: This website allows you to create digital designs that can then be sold on the platform. You'll earn a commission for everything that sells and you'll never have to deal with logistics like printing, warehousing and customer service. If you have some graphic design skills, then this is a great potential source for your web-based income.