FAST

Fair — be fair to yourself AND the other person. Don't sacrifice your needs entirely, but don't be selfish either.

Apologies — don't over-apologise. Don't apologise for existing, for having needs, for disagreeing, or for things that aren't your fault.

Stick to values — don't compromise your values to please others or avoid conflict. Know what you stand for.

Truthful — don't lie, exaggerate, or act helpless to manipulate others. Be honest, even when it's hard.