Don't wear a watch to the Renaissance, trust us on this one.
If you're visiting Ancient Egypt, be prepared for a serious pyramid scheme.
When meeting Leonardo da Vinci, do not try to sell him your 'latest and greatest' 3D printed Mona Lisa.
If you're stuck in the Dark Ages, just pretend you're a wizard, it's a classic.
When time-traveling, always bring a map, a compass, and a good sense of humor.