Spreading & Snugging:

If your bonsai has a pair of branches or trunks that are either too close together or too far apart and you can't separate them by wiring, these two training methods off a simple solution to the problem.

Spreading:
a simple wedge can permanently spread apart two branches that are growing too close. This works particularly well to separate parallel trunks and forked branches.
Take a small piece of wood, cut it into a triangular or trapezoidal shape, and gently wedge it between the limbs until they are separated as far as you want. Be very careful when separating forked branches; too much pressure can cause a split down the fork.
Remove the wedge after 4 months. If the branches return to their original positions, put the wedge back in place. Eventually the branches will lose their tendency to spring back when you
take away the wedge.

Snugging:
to bring branches closer, especially parallel ones, loop a soft cord or a small belt around them and pull them into the desired position. Or form a piece of sturdy wire into an "S" shape, hooking each branch into one of the curves of the "S". In time, the branches will stay in place on their own.