You can create an account for this year's amcas, Ibelieve. I did that a couple of years ago, just to see what was on there.
It's not really that big of a deal though.
Basically, you'll enter a bunch of personal info, input all your grades, put in descriptions for up to 15 ECs, and type in a personal statement that is something to the effect of why you want to be a doctor and what experiences you've had that support your decision.