{ 1 } - Follow the rules that would be most useful for society to adopt.
{ 2 } - Act only as you're willing for anyone to act in the same situation -- regardless of imagined variations of time or person.
{ 3 } - Perform an act of sort A (e.g., an act of lying) only if you want everyone to perform acts of sort A.
{ 4 } - Act according to your conscience.

The formula of universal law is a generalization of the golden rule. It also includes the self-regard and future-regard ideas. UL works more smoothly than GR if our action affects two or more people. Equivalently, UL says "Act only in ways that you find acceptable, regardless of where or when you imagine yourself in the situation."