Pruning azaleas

Azalea topiary

HTH

I really recommend against trying to topiary azaleas. It is their nature to regularly drop older trunks and put up new ones. If you put all your eggs in one basket -- leaving only one trunk, you could lose it all. I could suggest some pruning patterns if you are interested, but they must include leaving multiple trunks.

i think azalea pruning or manicuring can look good in some situations.
the cloud formation may be one style that you can work in, depending on the house and garden.
this style works better with azaleas with small leaves such as kurumes or satsukis rather than southern indicas.
on the other hand, i prefer the natural shape in most situations. if your azaleas have been rounded for years, you can start over by cutting them back severely (rejuvenation pruning) and maintaining them with regular selective pruning of branches and tip-growth to a natural shape that fits in better with the planting site.
i did this in april and will just have to wait a couple of years for flowers as they grow back. they simply outgrew the site and really should not have been used as foundation plants to begin with unless one likes the look of an azalea hedge.

Here is a link that might be useful: cloud pruning

Wish I had some good advice. I am doing a bonsai (I flatter myself by calling it that) on a maple. I just do whatever I think will look good in the near future. Experiment and learn.