You find out what your values are on the days they cost you something. Everything before that is preference.
Someone I know turned down a contract last year that would have solved a hard six months. He still thinks about the money. But he knows something now that no amount of self-reflection would have told him: where his line actually sits, in his case, in pounds.
Trusting your own nature gets easier once you have a few of those. They're the receipts. If you're unsure who you are, look at the expensive decisions rather than the stated intentions. The pattern is usually clearer than you expect.