Since all the materials needed are pocket-sized, I figured this would make a good entry for the pocket-sized contest.
Step 1: Draw flipflops on your feet with a sharpie.
Step 2: Don't draw attention to yourself during the visit.
If you are noticed to be barefoot, you may get kicked out by a security guard. If it's the security guard directly below, though, I wouldn't worry too much. He's on your side. And lazy, looks like.