Proper Edge Support
Framing at inside corners is often inadequate or lacking altogether, making it impossible to fasten the edge of the drywall (left). The solution is to inspect the framing before you start hanging drywall. Make sure there's at least 1 in. of exposed framing at corners. If not, add another 2x4 alongside the existing framing (right).
Especially check along the top of walls that run parallel to the ceiling framing. Normally blocking is nailed to the top plate of the wall during the framing phase, but it's often missing. If you have to add blocking and don't have room to swing a hammer, drive screws into the blocking at an angle from below.
Mark Framing Locations
If you forget to mark the location of framing members before you cover them with drywall, you'll have a hard time placing the screws accurately (left). For foolproof screw placement, make these marks and use them as a guide to draw a light pencil line across the sheet (right). Then you'll be able to place screws quickly and accurately. And you won't have to waste time removing screws that miss the framing.
Mark the location of ceiling joists on the top plate of the wall framing. Then mark the center of each stud on the floor. Make note of unusual framing so you'll know where to place screws after it's covered with drywall. After the ceiling drywall is hung, mark the stud locations on the ceiling with a pencil before you start to hang drywall on the walls.