I smell gas sometimes right as I am getting ready to get out of the car, or when I am sitting with the window down.

How do I check to see if it is my fuel rail, and if is is, how do you take it off, and is it hard???

I would'nt try taking the fuel rail off unless you know thats the problem. I would start by pulling the fuel pump cover under the rear seat, with the car running and see it you see any leaks, then work your way under the car with it running and follow the lines all the way to the motor. If there is a leak you will see it. If you dont find anything pull a plug and look to see if its wet with gas or smell it to see if its strong with gas smell. your plugs or ignition system may not be burning all the fuel.

That's the way to handle it. or you can go around your car after you shut it off and smell in the rear of the car and all the way around to the front. If you are leaking gas it will still smell after you shut it down. I walked around mine and ruled out the fuel pump and the fmu just by smelling. Then I just checked the connections of the lines to the rail and when they were good I checked the rail itself and found a leaking testport. The fuel rail is not "hard" it is a pain in the ass though and prolly around $100 to fix because they won't sell a junkyard rail without injectors. So start with the smaller possible problems and work your way up.

Most of the time, I smell it when the car is running, or when I just have turned it off.

Where under the back seat is it located???

Also,
If I drive it a little harder than normal, then I seem to smell it better.

Most of the time, I smell it around the driver's side of the car when the window is down, or when I am getting out of the car.

I smelled around the fuel rail, and didn't smell anything.