The easiest way is to set a Bid Group! On the page that lists your snipes, on the right hand side click on "new|delete" next to folders. This will take you to the screen where you can set a up a Bid Group. On the left hand side of this screen is a place you can click on for the tutorial for Bid Groups.
As long as the auctions all end more than a minute apart, you can set up a Bid Group. I've done this many times and it's a great feature. It allows your to set up several snipes for a particular item. AS will keep submitting your snipes on each successive auction until you win one of them. It will then automatically cancel the rest you have set up in the group. The tutorial should explain everything. Good luck!!