First, I would freeze time, then go to a department store, steal all the mannequins, take their clothes off (not in a kinky way, mind you) cover them in chunky tomato sauce, and hang them from the ceiling upside down. Unfreeze time for about 2 seconds, just long enough for people to notice, then freeze time again, take down the mannequins, clean everything back up and put the mannequins back where you took them from. Everyone in that store will be questioning their own sanity.
Also, a bunch of really simple things just to confuse people, like freeze time when a huge crowd of people are walking one way, and turn them all around, or go to a restaurant and mess with the busboys; as soon as they finish cleaning up a table put everything back exactly the way it was, over and over again.