I first read about tree shaping in a Readers Digest magazine in the 1990s. It featured a man who would shapes trees into chairs and other sculptures. Even since then I wanted to do it. I got started on a white cherry tree that started growing in my yard. Once it got large enough, I would braid and weave the branches every spring.
I didn't do anything as complicated as a chair. I would try to create loops by braiding two distant branches into each other and fastening with wire. Or I would take a long branch, and bend it back to the trunk, and braid it into a branch heading in the opposite direction.
The most difficult thing was not accidentally breaking the branches while braiding. Sometimes strong winds would create too much tension on the already stressed branches and cause them to break.
I did that for about 5 years before I sold that house. The tree is still there last time I checked, but I haven't gotten a close look at how it has progressed.
At my new house, I've tried it with a red maple, but haven't had much success. The branches that I've shaped end up dying.
Sharing this story makes me want to take up the hobby again. I've got some fast growing trees at my current house that I could use.
Edit: here is a photo of my tree (if you can abide imgur) https://imgur.com/a/PjwqWzo