Greeting to you and Horatio (from CSI?)
i had a very young Juniper that I wanted to shape quite early, and to start, I used a few big wooden beads (like little girls do to make bracelets and stuff) and it worked. However I prefer wire, because u can twist the branch the way u want to.
I dont know how how young/old your tress is so you might have to find something heavier, cos I'm sure Christmas balls will be too light....
Good luck
:)

Konnichiwa Hi-san to momiji Horeichio
(Japanese for hello Mr/Ms Fire and Horatio-the-maple)
(FWIW it is pronounced: koh-nee-chee-wah hee-sahn toh moh-mee-jee hoh-ray-chee-oh)

If Horatio is one tree - then your style is Sokan - twin trunk style (the smallest possible multiple trunk style). Soju is the style where two separate trees are trained together (a mini-clump so to speak). If they fuse over time, then it could be considered a Sokan.

I have seen all sorts of ingenious devices used to train branches - fishing weights, bread twistems and a bamboo pole, twine in a guy wire fashion, clamps etc. Use your imagination, but be cautious about damaging bark and cutting off the sap flow when placing and removing these devices.

As a traditionalist, I prefer wire to weights hands down. Proper wire technique will avoid too much wire, wrapping strand after strand around your trunk then up to the branches simply wastes wire.

The key with most deciduous species is that we don't use the older, harder branches so much. We cut the tree back, wire new growth and let the wire cut in a bit. That's right, let the wire cut in. Then remove the wire, prune the branches, and wire the new growth. As time goes on, the bit we wire moves farther and farther from the trunk.

This is what I am doing with my American elm in the link below.

Here is a link that might be useful: American Elm Development

BKC - Why would you let the wire cut in please - this is a definite first for me.

The wire breaks the sap flow so that callus will form in these area's allowing the branch to grow thicker must faster than it normally would. If the wire is removed at exactly the right time, no re-wiring is needed and the scars caused by the wire growing in will heal over time. You will get much faster results in this manner with much less wiring. Some people even wire young trees and let the wire grow in completely leaving the wire inside the trunk or branches.