The first step is to remove the interior handle assembly. There are several screws that need to be removed and the plastic cover removed. The handle is held in by a plastic clip. You have to pull hard to get the handle out. The next step is to remove the door panel. This is the hard part.
Remove the door panel using a screwdriver and then remove the handle assembly. To fix the door handle, you will need to purchase a new assembly and install it. The assembly may be held in place with a few screws, or it may just snap in to place.