Here is what I would do if it were my plant. first cut everything off that is dead or dying,cut all the straggly stuff off including all branches that have a couple leaves only. Wait about two weeks while watering and feeding as usual. Now I would remove that plant from the container its in and do some root pruning. Nothing too severe but enough to open things up a bit and repot it in a little wider but shorter container with good soil. New growth should start to come out and as this new growth becomes older, continue removing the overgrown stuff until you achieve the desired heighth with ect. this is not too complicated but its also not a quick procedure either.