There are several areas where you can make sure your garage door is functioning properly, especially if it's showing signs of wear and tear. Make sure all the moving parts are oiled or greased to reduce wear and tear. Check the tracks to make sure they aren't bent or broken and that the door itself isn't bent or warped out of shape. Finally, check all the cables and cords because these are critical for proper operation.
If you see any rust developing on your garage door, especially around ropes and springs, it's time to clean and oil them. The longer you wait, the worse the problem will get and the harder it's going to be to fix.