When the time comes, there will be a box that opens for the draft. It'll show all of us in one column, the players available to pick in another column, etc... When it's your turn to make a pick, you just click on the player, then hit the "draft" button or something. It's really simple, as is the whole game. Very intuitive.

You should be able to do a "mock" draft if you want to practice, as well. Just have a look around the site and you should find it somewhere/sometime. Sorry I can't be more specific, but trust me, people catch on very quickly with the Yahoo games.