Where are you? Generally speaking.
Remove the yellow foliage. Next thing is to go in and remove all of the old foliage in side, it win't have green growing tips or will be pointed down (dangling). Once it is cleaned and opened up it will help. Next, only prune to lignified wood, brown not green. Finally check with locals to see about fungicide requirements, or tell us where you are, and wstch outfor pedts like mites and bugs that feed on shoot tips.