There are 4 common methods:
1) Send the PDF to yourself as an attachment in email. Then, "open in" Adobe Reader using the option in the mail application.
2) Use a file sharing app like box.net, googl drive or dropbox
3) "Open in" after viewing a PDF in Safari
4) Transfer the files from your PC using iTunes as I describe in this thread: http://forums.adobe.com/message/4356013#4356013#4356013#4356013
Europe, Middle East and Africa