Here is my response to a post on BonsaiSite. You can read the whole thread HERE.
I don't think I have ever wired a trunk, or certainly not very many. I think it's much better to do it the way nature does it: trunk dieback, only we call it trunk chops. Wiring a trunk practically guarantees that you will never get taper, and taper in my book is just as important as movement. The only way to get taper from a wired trunk is to grow sacrifice branches, and they have to be in the right place: at the base of the bend or it will look unnatural. Chances are, wired trunks are going to look unnatural anyhow most of the time because rarely can you bend a trunk severe enough to make it look like nature did it, that is, with a trunk chop. Wiring may have a place with tall very slender trees where taper is unimportant, such as bunjin, but this is a very limited class. I think this is why you can't figure out what to do; snakey bends are just going to look like Chinese junk that have been wrapped around a bamboo pole. Another place where wiring a trunk may be appropriate is to wire the base of a young tree so that there is a very low turn. That's wiring in a single bend. This works because a tree will almost always buttress at the base and create the taper for you. Above this point, it won't happen. This is frequently done in pines, although low chops will give you the same effect with even greater taper.
One of my cardinal rules of bonsai styling is to trace out a trunk line using every branch of the tree. No low branches? That's where you start: do what's necessary to get them, which is using a higher chop to induce lower branching. This is absolutely essential in pines where once you lose low branches, they are most likely gone forever, but it's important for other species too. If you do this, you are already thinking and planning using principles of taper and movement. Changing the trunk line to make it go through a branch creates both movement and taper simultaneously. Everything above this point is junk except for its use as a sacrifice. If you are lucky, the branch/new leader will have secondary branching that will give you a another change of movement and taper. Rarely will you get a third section of movement from tertiary branching unless you have very advanced material.
How do you start? At the bottom of the trunk and move up. At the first branch, imagine that the rest of the tree is now gone and what the trunk would look like through that branch. You can manipulate it of course, most frequently by tilting the tree to make the base trunk come out of the ground at an angle and the new leader more upright. But you can also wire the new leader up or down to create less or more movement. Then imagine the next trunk section coming low off of this new leader. Is there a secondary branch there? If not, you will have to induce one.
Once this is done, put that image away and try another one. This time go up the trunk PAST the first branch (which will probably serve as a sacrifice instead) and imagine a trunk line through the SECOND branch. Is this better or worse than the first image? Then with the third branch, and so on. Probably ninety percent of the time you will use the first or second branch. Now the stunning realization of this is that when you are looking at raw material, the vast majority of the wood and foliage you are staring at won't even exist in the finished tree! Hopefully, this will change your perspective when analyzing potential material.