I can only speak from my own experience and what I've seen, but generally the best leaders are the ones who emerge naturally from within the team. You shouldn’t need to "prove yourself" to your superiors but to your coworkers instead.

Most teams don't want or need a boss, they need a leader

I don't know what your "vision" looks like, but start small. Feel like some manual task could be automated? Write a script and share it with the team. Think something should be done differently? Bring it up and see what others in the team think. The point is, you don't need actual "power" within the company to start implementing your vision. Unless of course the company culture is just horrible, in which case you'd probably be better off looking for other opportunities regardless..