Steer towards where you look and that's where you'll go. That's basically the technique for whether you're parking, cruising down the freeway, racing, drifting etc.
Line the rear of your car with their's. Then turn the wheel inwards (ie towards the car) all the way. When your mirror is in line with their rear, turn the other way slowly and adjust. Make sure you don't hit the car in front or behind.
And who cares if there are people behind.