Here are some tips from an Aspie University Senior.
For paying attention, I would write as much as I can down. Even if you already wrote it in your notebook earlier, it still helps with remembering it and finding it to refer back too. I would also recommend getting a voice recorder of some kind. I have one and it has done wonders for me. You'll need to get accommodation letters from your schools disability services, which will require you to submit proper documentation of the Aspergers diagnosis or anything else.
For socializing, the best advice for this would be to join a club. If you look or inquire a bit, you will be sure to find a club that relates to an interest of yours. I am in the IMPROV club and the gaming club at my University. It is a great way to meet people that share similar interests. I would also say that if you have picked a major, it is likely that the same students will be taking the same classes as you, so that is another option. Also, take advantage of any campus events that you can make it too. Even if you don't necessarily socialize, at least your face is out in the open so some people may recognize you.
Hope that's helped you out some. If you have any other questions feel free to ask me or PM me.