How do you set up an affiliate marketing program for a website you own?

Figure out how you want it to work, and write web software to support it. Get people to sign up to refer people to your site. Pay them what you say you’ll pay them.

If you ask a more specific question, you will probably get more specific answers.

sign up with Google Adsense, but don’t expect to get rich.

yeah, but aren’t there already programs that take care of affiliate marketing for your website? what are the names of these programs if you know of them?

http://www.cj.com/ is one I have worked with in the past.