Meta tags (title, description, keywords), keywords in H1, H2, H3 tags, keywords in content in <strong> and <b> tags.
Making sure your website is ready to go code-wise will help put you on top. Having quality content is obviously a major factor but isn't a must-have for making a steady income online.
If you did not developed website then first start to make SEO based website with user friendly , then invest some time to visit your target industry websites and try to get domain name which include your target keyword then research on that keyword then make quality content and use that keyword which you want to target but content should be unique then do some internal links then make title , description for your website then start do some off page work.
first think about user, then for content and lastly for keywords and meta tags and other things. site must be user friendly that is most important thing.