Gene,
Pruning and training to a bush form is basically the same as the tree form except that the main trunk is cut very close to the ground in the second season of growth. The first step is to establish strong roots and a large caliper single main trunk in the first season by training as a single main trunk plant, then cutting the trunk in the second season down to 4" - 6" above the soil line. The fig plant will then produce shoots in a spiral on the 4" - 6" main trunk. Select 3 - 4 branches and train as the main scaffold branches.
Attached is the Japanese Container Tree Form diagram that was posted in a pruning topic ( http://figs4funforum.websitetoolbox.com/post?id=6388743 ). It has been modified to "Bush Form" by editing the dimensions in Step #1 and Step #2...
Pruning to Bush Form:
Step 1. Establish a single, straight main trunk...for the uninterrupted flow of nutrients to the scaffold limbs and fruiting branches.remove all side branches and figs that form on a rooted cutting less than six months old. Prune the main trunk @ 6" when the trunk caliper is 1" or larger.
Step 2. The main scaffold limbs have to be spaced far enough apart vertically on the Main trunk for future increase in caliper size, which means that they need to be 1 node apart. Select 3 - 4 scaffold branches and train at 45 - 60 degree angles to main trunk. Prune at 40" at the beginning of the growing season to remove apical dominance and induce branching.
Step 3. The secondary scaffold branches that are selected and allowed to grow have to be separated by 8" (2 or more nodes) for branch caliper increase and for the growth of future fruiting branches, which are also spaced 8" apart. The main scaffold branches are lengthened by 16" and the apical tips are pruned to induce branching on the extensions, fruiting branches are then allowed to develop 8" apart.
Step 4. The fruiting branches are pruned back yearly to 2 one year old buds (nodes) for the next seasons fruiting branches. The fruiting branches are located at 8" intervals along the secondary scaffold branches. at the fruiting branches Only one bud is allowed to grow the other is removed.
Here is a picture of a 1-1/2 year old Fig tree pruned in the Bush Form. All visible growth is 1 season old.
Good Luck.