You'll receive an email soon. In it there will be a link to download testflightapp, which is a beta testing app loader (no jailbreaking or anything of the sort). Receipt Loader will be in the dashboard, and you can download it from there. After that an icon will appear on your screen light any other app, and it will function like any other app.
Got my email, but no link, confirmed my subscription, but no link. What gives?