There's always the bus. Many people rent motorbikes too. In fact the bus station is right by the motorbike rental shops so if the bus is too crowded just rent a bike for the day. But once you rent a bike they are hard to give up. Just be careful because not everyone is as good a driver as you are. In fact there are people on motorbikes (and cars) that should never been granted licenses... if they actually have one. If you drive at night you have to assume that just about everyone on the road is drunk.