Why leave no branches?

Wait until the tree is dormant (has dropped it's leaves) before pruning, and then just take out the poorly formed branches that affect the over all form. Never remove more than 50% of a tree at a time. Look for branches to remove that are dead, diseased, drooping (unless you have a weeping form tree), crossing other branches & rubbing, and are growing at a 90 degree angle from the trunk (weak connection). Also, thin out branches that are all growing from the same place. Definitely get rid of any suckers or water sprouts.

Much debate in the arborist world about topping trees. If you do it, you are going to ruin your central leader's chance at growing straight and tall.