In general, most people don't care much about strangers. The first assessment, usually unconscious and automatic is to file a new person into one of four categories: friend, enemy, potential sex or life partner, and neutral, or of no interest or signifigance.
So if you're polite, fair, honest, responsible and reliable towards everyone, you'll never have an enemy. If you make a mistake and then immediately own up to it and make amends, most people will forgive and trust you.
If you already do this, or if you can make it a habitual way of beng and living, you'll never need to worry about what people think.
The majority of people do form relatively realistic perceptions based on their direct experiences with you.
That said, we can't fine tune or control the thoughts and reactions of others: there will always be a subtle alchemy based on personal preferences.
If you're a public person, all that gets harder because it's driven by media and likely to be distorted - and that's a good enough reason to prefer a very private life - at least in my view.
