How do i get the battlefield 3 beta?

i got the medal of honor limited edition for ps3, and it says on the case that i can get early access to the beta of battlefield 3. how do i get the beta? and when can i get it?|||It's coming out next month! I think you just have to be signed up for it on their site, but I'm not sure how they select. I think it's random draw.|||The beta will come out this September, no specific release date yet.