Step 1
Cut a cross through the burn mark with a scalpel or very sharp knife, and then cut the burn out by cutting a circle around the cross. If the burn didn't make a hole, dig the scalpel only about halfway into the leather and remove the damaged layer. If the burn made a hole, cut all the way through the leather to make a larger hole than the one made by the burn.
Step 2
Patch a hole with a piece of canvas cloth large enough to cover it, and leather glue. Insert the cloth through the hole with tweezers and spread it out behind the leather.
Step 3
Dab leather glue -- which comes in the leather repair kit -- onto the back side of the leather around the perimeter of the hole with a scalpel. Push down to press the leather against the cloth; wait for the glue to set. Check the glue container for the proper setting time.
Step 4
Fill the hole with several light coats of leather filler. Spread a thin layer with a palette knife, and clean the excess from around the hole with a cloth. Then heat the filler with a hair dryer set to medium heat for three minutes. Wait another three minutes, and apply another layer. Repeat until the top of the filler is almost flush with the leather; after that, you need one last coat.
Step 5
Spread the final coat of filler, and before heating it, imprint the grain with a grain embosser. Use one of the grain patterns that come in the repair kit or a small piece of the same type of leather as the one you're repairing.
Step 6
Sand the repair with 600-grit sandpaper after the filler has completely dried to erase the edges and feather them into the surface of the leather.
Step 7
Color the leather with colorant, a thin paint that matches the color of the leather. You may have to pre-order this from a leather repair professional to make sure you have a matching color. Apply two or three thin coats with an artist's paintbrush to make sure the repair is completely covered.