For most the technique of putting the right foot in first, then your butt, and finally swinging in the left foot, works best. One thing to keep in mind though (especially if you are a little heavier than you used to be) is to minimize the twist on your left knee as you are getting in and out of the car. There is actually a medical condition called "sports car knee" that occurs when twisted knees are loaded too heavily. I'm told it is a very painful condition that affects walking, standing, and even throbs when you sit or sleep. A Corvette owner friend of mine had it last Summer and he was in real misery. The best way to avoid it is to try to keep your knee straight and use the steering wheel and door frame to support your weight as you are getting in and out.