Don't Spam
Don't spam EVER. This means no unsolicited emails, forum posts, blog comments, and also no spam directly in your website. Lists of keywords, hidden text, etc are all bullshit methods and will only get you blacklisted by search engines.
And that's it. This is a simplified guide, but should get you started, or perhaps help you in a key area where your website and affiliate marketing strategies were lacking. Good luck and don't forget to have fun with it!