I land in Gatwick at 845, then take the train to London bridge station and drop my bag there and then continue my way to trinity square to have a haircut at 10. At 12 I have a meeting at Southwark bridge. Meeting ends at 2 and then there's another meeting at the Shard at 2:30. Then leave just before 5 and catch the train back to Gatwick to take my flight back, which departs at 6:45.
I can stay overnight (as I think catching that flight back might be a bit too risky). I wouldn't have anything with me beyond my handbag with my laptop.