Before you start, get fire extinguisher, large container to catch old gas, other containers to dispose of old gas, new fully charged battery.
1. Drain the fuel from the gas tank or remove gas tank and flush it out. Under NO circumstances use the gasoline that's in there.
2. Remove spark plugs, squirt a very light oil or transmission fluid into each cylinder---about 1-2 tablespoons in each. Let sit for a few hours or overnight
3. Turn the engine BY HAND if you can (using socket on the crank pulley, or if you can't, disconnect ignition coil and crank with the battery. Under NO circumstances put a jump start on the old battery...dispose of the old battery completely and use a new one or good used one.
4. Drain engine oil, change filter, and install fresh gasoline.
5. Check coolant level, fill up if necessary, you will flush this later
6. Hook up coil, try to start engine. Watch for gas leaks, have extinguisher handy.
7. If engine starts, let it idle for a few minutes, evaluate if it seems okay (it may smoke a bit) WATCH the temperature gauge.
8. If engine seems okay, let idle, check transmission fluid (if automatic). Shut engine down.
9. Pump up tires, start car, back it into driveway. Continue to let it idle, look for leaks anywhere.
10. Drive car up and down driveway, test brakes, steering etc.
11. If the car seems to start, stop and steer, take it to a service station to flush coolant, flush and bleed brake system, check all hoses and belts and carefully check tires for age, cracks, leaks.
12. Once caris deemed SAFE, go for a test drive and sort out defects as you note them, and fix as necessary.
Work SAFE, stay alert, TAKE YOUR TIME, and don't start putting expensive parts on the car until you're sure the engine and transmission are functioning, and don't go for a test drive until you have made the brakes and tires safe to drive.