Your name is a brand you build every day, one interaction at a time. Nobody gets to rebrand overnight.

Reputation is not something you announce; it is the average of how you have behaved, held by everyone who has dealt with you. Each interaction is small, which is why nobody notices it forming, and also why it cannot be reversed quickly. People who try to reset how they are seen usually find that one good month does not outweigh two bad years. Consistency is the only available method.

Pick the one behavior you would not want described to a stranger and change that first. Then keep it changed for longer than feels necessary. Slow is the only speed this moves at.