Best advice I ever got was to treat myself like another person.

Hopefully most of us already have a handle on the golden rule, and treat others the way we want to be treated, but I think a lot of us (especially ambitious people) are pretty hard on ourselves, even though if someone else was going through what we are going through we’d show them compassion and understanding. So ask yourself how you’d treat someone else, and then treat yourself that well, you deserve it.