Open the door until the screws holding the hinge to the door and door casing are fully exposed. The door should be at a 45-degree angle to the door casing.
Slide door shims beneath the door until the door is braced up at three points. One point will be beneath the latch-side of the door, another point beneath the middle of the door, and the third point beneath the hinge-side of the door. Use a hammer to drive the shims under the door.
Loosen the screws in the middle hinges. Unscrew the screws on the door-side hinges first, and then the screws on the door-casing side.
Loosen the screws in the bottom hinge. Remove the door-side screws first and then the screws in the door-casing side.
Ask someone to hold the door while you loosen and remove the screws in the top hinge.
Open the door.
Squirt anti-seize corrosion solvent spray in the grooves of each hinge where the hinge pin holds the hinge together.
Open and close the door several times to allow the solvent to work into the hinge shaft pin housing. Clean grime out of the hinges with paper towels.