Finishing Inside Corners

Coat both walls of the corner with drywall compound using a 6-inch knife. Fill any gaps between the two walls.

Unroll a length of drywall tape, the longer the better, but you may have to experiment to find a length that is easy to work with. You can cover the corner in several strips, overlapping the ends. Fold the tape in half, as shown, along the crease made by the manufacturer.

Stick the tape in the joint compound pushing it in place every 12 inches or so. Draw a knife along each wall to press the tape into the compound and remove excess mud. Let the compound dry overnight.

Apply joint compound to one side of the corner with a 6-inch knife. Feather the outside edge and let it dry overnight.