Well going by the skill level of some of the people who just graduated from my course, f**king nothing.
First year was spent going over the BASICS of PS/Illust/InDesign. Some of these people had never even seen a Mac let alone used one, same with the software, however I'm sure things would be different at a decent uni.
I did a BTEC ND in Graphic Design at College, then went straight to Uni, so obviously I had some skill, I would have said if you're of a standard now where you can "design" things then you should be okay. If you go along with a portfolio you should get in easy enough, that Heatsink shirt will help quite a bit