1. Find a niche you want to promote.
2. Build a website over the subject
3. Sign up with CJ + other networks.
3. Learn basic seo and get decent listings for your site in the SE's
4. Cash your checks
5. Send me a fat cut for helping you out

This post could be a real help to people that are new to affiliate marketing, so I'll attempt to explain in more detail;
1. Find your niche
Find a subject or product that you're interested to work on. It should probably be something that interests you a bit as you'll spend a fair amount of time with it. (Suggestion: stay away from digital products if new to Aff marketing)
You can also look into the market by checking traffic volume with keyword research tools
e.g.
And also look at the sites that rank in top ten.
Check how many backlinks they have.
put the URL in google (not very accurate) and also try the Yahoo site explorer
you don't want to pick something too competitive (like viagra) or with no traffic at all
2. Build a site - I recommend you get your own
hosting and URL. It doesn't look good if you use Geocities or a free account.
3. Signup with affiliate networks
/forum/the-big-3-b18.0/ - Commission Junction (CJ), Linkshare, Shareasale
More at /forum/other-ad-networks/affiliate-network-list-t12.0.html
4. If this needs further explanation, just PM me for an address and you can forward them to me
5. This was a misprint. See #4.
A few things for beginners...
Settle on a topic and jump in.
It's easy to get caught up in analysis paralysis.
You could study a topic for a year and never accomplish anything.
I'd suggest a week is more than enough time.
As a (very) rough timeline...
Look up some topics for working on
(you'll start to get ideas when you're signed up at affiliate networks and look through all the categories)
1 week
research your chosen topic
1 day - 1 week
build your site (including seo-on pages)
1 day - 1 week
build links
ongoing
So if you find a topic and it looks good, you should have signed up at a program and built the site within a few weeks.
After that, you're busy building links and traffic.
If you're unsure about SEO, I highly recommend the
SEO Book for beginners and even intermediate web marketers.
It will save you a lot of time instead of trying to learn from forums and blogs, which is fine, but there is a lot of bad info out there too. Well worth the $79 asking price several times.
One final note - when you start link building, work on keyword phrases that are 3, 4, and even 5 words in the phrase to start. you can mix it up and include 2 word phrases (mixing it is always a good idea) but to start you're best off to go after the easier stuff and work your way up
Hope some of that helps!