Most bike courses are closed, and the courses are very clearly marked. Most sprint distance race will NOT have water on the bike course, so make sure to have a bottle or two on your bike. It's also a good idea to carry a bike pump and patch kit in case of a flat. Watch that you don't draft, find your pace, make sure to keep drinking. I like an aero bar mounted drinking system. Snack on a gel or powerbar. Look at all of the cool bikes, enjoy the scenery.