How to Apply Joint Tape. Taping and "mudding" Sheetrock (drywall) is a process that requires practice - and if you're doing a whole room or a whole house you'll get plenty of that. The first coat is the tape coat - here's what to do.
Apply Tape to Joints
Choose your weapon. Taping a joint can be done with two different types of tape: paper tape or self-adhering mesh tape.
Apply adhesive mesh tape directly to the Sheetrock, centering the strip of tape over the joint and pressing it firmly to the surface.
Apply paper tape a bit differently: Load your 4- or 6-inch taping knife with drywall compound (mud) and apply it in an even thin coat along the joint; then take a length of the paper tape and press it into the mud with your knife.
Make sure that the tape (whichever you use) is smooth and that there are no air bubbles under it.
Apply another thin coat over the top of the tape. You should still be able to see the tape through the drywall compound.
Allow this to dry completely before applying additional coats of drywall compound. (You won't need to apply additional tape.)
Apply Tape to Inside Corners
Press adhesive mesh tape directly into the corner. Make sure that the tape is evenly shared between the two walls.
Apply paper tape with a mud bed, as described above. Spread a thin layer of mud into a corner joint with a trowel. Fold a length of tape in half and press its fold into the corner. Run corner trowel down middle of corner to press tape into mud and work out excess mud.
Spread a thin layer of mud on top of tape using corner trowel.