As a long-time rural driver with twenty miles of prime white-tail habitat between my home and the nearest town, the best piece of advice I can offer city folks who find themselves driving in deer country is this:

Deer often travel in herds and family groups. When one deer makes it safely across the road in front of you, it's not a signal to speed up and be on your merry way. It's a signal to slow down and proceed extra cautiously because there's a good chance more deer are going to be following it.