Cannbosh, looking at the picture, the for sure dead leaves need to be snipped off, then do like andycapp suggested, what type of nutrients are you using, what type of setup, hydro, soil?...what type of light,...there is a lot that needs to be known to give any help... but definitly first snip off those dead leaves so what you plant needs is going to the good branches not trying to save the dead ones,..second, depending on how the branch snapped, completely off?..or just bent? did it break the outer skin of the brance?...I do super cropping so if you only bent it real good it will be fine, if it broke the skin get a piece of duct tape and put a bandage around it to help it heal, if it completely broke off and would make a good clone then clone it...hope that helps a bit