Step 1: Upload Videos to YouTube.
Step 2: YouTube rolls out profit sharing plan where they reward uploaders with shares of ad sales based on number of views. The ads will come in the shape of short clips in place of the actual YouTube video, which you presumably have to watch before getting to the meat. The videos may be at most three seconds long, but the details are still being worked out.
Step 3: Profit.
YouTubers to get ad money share [BBC - Thanks Adrian!]