Help for low elo player?

I need help. I'm at 850 elo (I know bad) but I was at 1200 then I kept losing. Yeah I keep neutral or negative but that's because either support is terrible (I mostly play AD) or I will be winning lane and the rest of my team loses their lane. I'll admit sometimes I do bad but most of the time I will be doing fine and my team will lose it. Any advice for me to carry my team or just simply play better and get out of this terrible elo?