Insert a screwdriver into the screws in the hinges of the shed door and the door jamb itself. Twist the screws to the right to tighten them. This action is often all that is required to lift the large shed door up where it no longer drags the ground, sags or sticks.
Open the shed door and then shut it to check if it works properly. If not, ask an assistant to help you make further adjustments.
Remove the middle screw in the hinge of the door jamb while your partner holds the door level. Starting with the middle screw and replacing them one at a time makes the task easier.
Add a 3-inch screw to the hinge with a screwdriver. These work well for large, heavy doors and are better at supporting the additional weight. Do this one at a time until all the screws in the hinges are replaced.
Check the shed door to see if it operates efficiently. If it works better, but still tends to stick or sag a bit, add a 3-inch screw about 2 or 3 inches above and below each hinge. This causes the wood to fit more snugly inside the frame and makes it less likely to sag in the future.