What does 'put a jinx on your bid for stardom' mean?

A jinx is an unlucky person, thing, or situation. It is related to the superstitious ideas of "bad karma" and "evil curses". (e.g. losing a sports game because you wore the wrong socks)

What the person is saying is that something will bring misfortune to the person trying for fame and celebrity. This could be coincidence or a deliberate antagonistic action.