1. Pick as many keywords as you want (but less can be more (I do no more than 25, typically 10-15) for your html meta tag(s) most important keyword first to least important—>no repeats (maybe get Google-Slapped if you do?), Front load your keywords in html title tag(s), html H1 tag(s), 1st few sentences in first paragraph, alt tag(s), url (url keywording importance waned/died in 2010—>in fact, over optimizing/key word stuffing your url can be penalized by Google these days).
2. Make your content readable/desirable by humans, and search enginges. Decent to great content for humans is the lowest end of the spectrum. Amazing life changing content for humans is the goal. Then, a few technical twists, and the search engines love it too.
3. Inbound links from reputable sites in your niche, influencers in social media, blogging, and video.
1. Google does not like over optimized pages. Anything link building-wise for example that someone would normally not do (like buy 1,000,000 links to your site in one day) is usually frowned upon.
2. If you piss Google off, you may have to go to court to try to get your site to show up in search results. Most people have lost this battle. I don’t know anyone that has won in court against Google.