As a black person in tech, imposter syndrome is a big part of reality for me. It doesn't help that I've had people straight up tell me that they expect less from me. Things that help for me are

• Journaling, especially maintaining a "brag doc" of accomplishments (from big to small, anything that puts a smile on my face or gives me a tinge of pride)
• Perpetutally seeking out (and providing) constructive feedback. This has the dual purpose of 1) providing validation, which should become less important over time as you become more sure of your self, and 2) calibrating expectations. More on that in the next point
• Being explicit about expectations - both my expectations of people and people's expectations of me. It would be difficult to have a fair assessment of yourself or push back on someone's unfair assessment of you if you don't even have a baseline of what to assess.

It is also immensely helpful to be mindful of these facts

• People's assumptions about you often have more to do with them than you. You have no obligation to play along in those games.
• Everyone is allowed to grow, learn, fail, make mistakes, and try again. When the penalties for failure are unfairly higher for some people than others, that is a problem to fix, not something to normalize