What needs to be done if a car has been sitting in a garage for over a year?

If the engine has not been run or turned over in that time, do this. Remove the spark plugs, and pour ordinary motor oil down the holes. No need to fill them, but pour some in there. Let it sit overnight. Hopefully the battery has been disconnected all that time. Put it on the charger. The following day, turn the engine over by hand, not with the starter motor. When it feels "free", install new spark plugs, re-connect the battery, and cross your fingers. If it starts, it's going to smoke like hell, but don't worry about it. Do not attempt to put the car in gear until you're sure the brakes work. Then apply the brakes, put the car in gear, and slowly release the clutch. If it's an automatic, run the transmission through all its positions and wait for it to take up the slack and engage. If everything is now working, drive it out into the daylight, let the engine warm up, and do a "circle check" around the car to see that the tires are good, pumped up, all the lights work, etc. Good Luck.