Open and close the gate a few times to determine what repairs are needed. If the gate is difficult to open or close try to determine what causes the problem. Look for loose bolts or screws that need to be tightened.
Tighten the bolts in the hinges both in the post and in the gate. If the hinges have bolts and nuts, be sure to use one wrench on each side of the gate to tighten them. Replace stripped lag bolts with bolts 1/4 to 1/2 inch longer than the originals. Test the gate once all bolts are snug. If this fixes it, return the gate to normal use.
Check the post for level. If the gate is attached to a wall, tighten the fasteners. For wobbly posts, drive sharpened stakes made from treated 2-by-4 lumber in beside the gate on the side it is sagging toward, typically the gate side, to shore it up. Test the gate once the post is level and secure; if it functions correctly, return it to normal use.
Straighten a sagging gate by installing a lift kit. Use a framing square to determine if the gate is square to itself. Lift the gate to adjust it if needed and tighten all screws or nails in the gate itself. Install corner brackets of the gate lift at the upper corner of the hinge side and the lower corner of the latch side. Consult installation instructions with your hardware for specifics
Attach the aircraft cable to each corner bracket with clips provided. Attach the ends of the cable to the turnbuckle in the center of the gate. Use a wrench to tighten the turnbuckle to lift the gate. Lift it just a little past where you need it. Cables have a tendency to drop slightly as they settle. Test the gate and adjust further if needed.
Adjust and tighten the latch to insure proper operation.