Together with the Three Refuges, what moral principles should a Buddhist follow?

A follower of the Buddha should also follow the moral principles set out in the Five Precepts. Namely they should abstain from killing, stealing, sexual misconduct, lying, and using liquor, alcoholic drinks, or intoxicants that cause heedlessness. They do this by acts of loving-kindness, generosity, contentment, truthfulness and mindfulness.