Try to avoid wiggling the hook to work it back out. This puts more stress on the fish. For most of the lip hooked fish that I catch, I can grasp the hook with a pair of pliers, and while holding the fish in the water, twisting my wrist to simultaneously unhook and release the fish. Try to avoid holding the fish with your hands because you will wear away his protective coating. I'll explain more about this in a minute.
Some anglers use barbless hooks, or crimp the barbs down with pliers.
This makes unhooking a fish quick and easy. If you know how to retrieve a fish, you won't loose any fish because your hook lacks a barb. When unhooking a fish, the longer it takes, the more stress you put on the fish. It also applies to fish just as it does to humans, only more so. The longer a fish is out of water, the less his chances of survival.