If you have recently moved a door hinge from one side of the door to the other, then you may find that you have some very large holes left in your door frame. If you want to cover over these holes, then you can do so quickly with a few simple household tools.
Step 1 - Fill in the Hole
Before you can fit any covers over the holes, you will first need to add some caulking to the wood, in order to prevent the wood splitting during temperature changes. Use wood caulking, and place it inside the holes. Leave to dry.
Step 2 - Fit the Wood
Take a plain piece of wood, the width of your door, and cut it down until it fits into the shape left by your former door hinge. This may include covering over any wood stains left by the hinge. Once the wood is the right size, glue the inward facing side, and then press it into place. Hold until the glue starts to dry.
Step 3 - Finishing Up
When the wood glue is dry, sandpaper the edges until the cover is flush with the side of the door frame.