It's really a matter of personal preference after some preliminary trimming of any branches that are growing horizontal or down. (Dis)proportional cutting is one school of succulent shaping, but you may have your own ideas. If you search for 'Jade Pruning', 'Whacking a Jade', 'Trimming a Jade', 'Doing the Chopadopoulous with Crassula Ovata*', you will find information ad infinitum. Just search the Forum here Any thread which has lots of replies about whacking would be my first suggestion. You will have lots of pictures (befores and afters even!) and advice / experiences to read about. *Note that that last suggestion will likely not have any hits

It needs sun and possibly less water. What's your zone? (the photo downloaded right side up - nice plant).

I have had branches fall off of a jade tree before. It generally left a clean 'scar' on the trunk or branch. Like this - When that has happened, my plant was too wet. It can be a problem for me during the wet and rainy summers with high temps (which can also cause the jades to sort of shut down for a little while). You may want to be sure your pots are drying out well between watering intervals. On the left side you can see where I had trimmed a branch. It is rougher, but healed over well. You can get new growth from that area where the branch was jettisoned. (a different plant here - I guess I've had it happen a few times!) And of course, after pruning you will get new growth. This jade plant looked similar to your plant. Its branches were shaky or bouncy or floppy acting, too, because all the leaves were at the end of the long branches. So I gave this one a good whack. It looks pretty good now - about a year later. You can clearly see a pruned area that has branched with new growth on the upper right. Like Rina said, I like to leave some leaves on the plant when I give it a good whack. I don't think it is necessary, but I feel like the leaves help feed the plant and lead to a faster recovery. And after the plant recovers from the first cuts (as marked by Rina or others of your choosing) and start showing new growth, you can go back and prune more from other branches if you choose to do so. I have the advantage of keeping my plants outdoors all year long. So adequate sunlight is not a problem. Be sure you are getting the best light available during the winters. If it can go outside during the summer that would be great. Just introduce it to full sun slowly so it doesn't burn. Good luck! I'm sure things will work out fine for your jade.

Kim Just few things to add: Best time to prune plants is during their growing season/period. That would be few months later. I have good experience with jades, and pruned them any time of year, without any problems. That may not work so well with some other plants (will not, usually, kill them but may set them back), but jades are very adaptable. All plants grow better during their active period. Should you decide to wait, your plant will grow some. If you can increase light now, new growth should be more compact = sets of leaves growing closer together. If that is the case, when you eventually prune, do not leave long etiolated parts on cuttings. It may mean that you would cut some branches couple of times: 1st when you prune it off the main branch, and 2nd time to shorten it. Actually, any piece of it will likely root if you want, including extra leaves (as long as they are healthy). Just be aware that you could end up with too many jades ! :) Embothrium mentioned: ..."if it were mine I would try moving it into stronger light without whacking it back, seeing what happens"... That is ok, but there is no question as what happens: etiolated growth will not revert to compact, and your plant is plenty etiolated. That's why I suggest to shorten up cuttings if you wait. OTH, some ppl may like long, bare (or sparsely leaved) branches, with compact, almost pom-pom top - so decide what you like. I have few plants that have, probably, trunks that are too long. Another suggestion I have is to cut close to a "ring" on the stem. I usually leave just couple of mm beyond. If you leave long stub beyond the 'ring', it will take long time before it dries up.