To style bonsai,
There are several things to keep in mind to style bonsai. (reading bonsai branch rules may help you to understand which branches should be removed.)
1. check your tree from four different sides and decide which side should be the front.
2. check which branches you want to remove.
3. before you remove branches you must know what kind of branches should be removed.
3. when removing a branch you shouldn't cut all of it first. (Cut the remaining for a better way. Ex, you can make it a Jin.)
4. the balance of the shape is always important
5. A way to make the balance, you may want to follow this basic technique : cut the long branches and leave the short ones.
How to make bonsai styles
As each style has its own rules, you may want to apply them when styling your own bonsai.