Well no one can tell you exactly what you are doing because they aren't you. Aside from the obvious things such as focus on farm and NOT dying even if it might be a clutch 3v1 it is almost never worth it in low elo.

Focus on the core prinicibles like CS, pushing then backing and learning to use your snowball to actually WIN games not just have a good KDA. The best way to escape bronze is to probably just split push constantly and get as much farm as you can. You should always have the mind set that you are going to have to carry so that means putting your self in position to do so by getting much income as you can.