Yikes! After I read "orbital buffer" I thought what kind? After I read "Turtle Wax Rubbing Compound" I said to myself "oh...no...

". After I read "styrofoam bonnet" I thought

.
First off, stay away from the Turtle Wax Rubbing Compound. If you're shopping at Wal Mart, Pep Boys, Autozone, and etc get yourself a Meguiar's No.2 or No.9 polish. They're pretty much several of the best polishes you can get off the shelf. Use a 100% cotton terry towel, fold it into 1/8ths and use even, firm pressure. Make sure to go in a straight line and follow the aerodynamics of the car. That means go left to right on the hood, roof and rear deck, and go up and down on the sides.
What kind of buffer are you using? And what's a styrofoam bonnet? Bonnets are usually used to remove waxes and polishes, rather than used with polishes to remove swirls.
You don't want to exert uncessary downward pressure on the surface of your car. That means let the product work itself, rather than you doing all the work. At most, you should exert no more than about 10lbs of pressure in addition to the weight of the machine. The key thing to remember is to let the product do the work, not you.
How often you move depends on how deep the marring is in the clearcoat. Obviously a surface in severe condition will require slower movement, whereas a surface in top-notch condition with very little swirls and marring will not require so much work.
Here's a diagram of how the passes should look:

[list=1][*]Red[*]Blue[*]Green[*]Purple[/list=1]
You want to do it evenly and start off with letting the weight of the machine do the work. Apply the product and spread it around with the machine, and make sure it's turned off so that you don't splatter it all over the place.