In low elo it can be beneficial to play champions that can create a lot of pressure on their own unless shut down by team coordination. Of course a lot of these champions have higher skill caps or have harder lane phases and just scale super hard.
Playing a champion like Nasus, Tryndamere, Jax, or even Xin Zhao that create a lot of pressure just by staying in lane and split-pushing (make sure you keep vision and avoid being ganked) can create openings for the rest of your team by drawing pressure towards yourself. If you get ignored you can just quickly take towers and eventually inhibs as well. Make sure you farm efficiently in lane, and if you are taking teleport make sure you use it efficiently (if you don't know what would be the best times to use it it can be better to just grab ignite or exhaust).
Your bot lane should over the course of most games go about even (you'll have games where they win hard and games where they lose hard but over time those SHOULD average out). And so you just have to apply as much pressure and contribute as much as you can to the wins. Make sure you don't give anything to your lane opponent for free, and if you are getting camped by their jungle you can just make sure to stay alive and farm as much as possible. Make him waste his time trying to shut you down and hope your jungler can take advantage and pressure bot lane/dragon.
A split pushing Jax, or a hard farmed Nasus can win a game pretty much on their own in low elo. Tryndamere can be a nightmare once farmed and split pushes like a monster and if they don't efficiently CC you, you can shred their carries in fights (he is the only champion I take Cleanse on in top lane if the enemy team grabs someone like Lissandra). Just become a nuisance for any team to deal with, and until you start climbing to higher divisions it should start winning you more games than you lose.
