If you show up on time, everyone will be sitting in a conference room right in front of the door you enter (Medical Science Bldg II, I believe), you can't miss it. Otherwise just pop into the admissions office (just to the right of the conference room) and they'll give you directions.
I just followed the other college students in suits! But the directions they give you on how to find the building can be misleading - there is some construction that doesn't let you enter the road you need to get on if you're coming from a certain direction (going down the hill). If you have time, scope it out in advance.