First is it a well established tree and are you happy with the thickness of the trunk? If not then let the thing grow wild. If you are happy and it is healthy and ready to go then pinch, snip, cut or whatever you desire to shape the tree. These things grow like weeds and will backbud all over the trunk and branches, so you have almost infinite control over what will develop. They are also so apically dominant that you won’t have any problems with developing the apex. For the best info on dveloping them go to Zach Smith’s bonsai-south.com website, he is the man when it comes to these!