You'll need a random orbital buffer. Light brush going against your car is going to leave swirl marks/spiderweb looking scratches in the clearcoat - easy to remove. If it looks like the car was keyed, those aren't going to change. I'm guessing your truck is black, red, or blue.
Get a random orbital or borrow one from a friend - you'll want a 6" version. Porter Cable 7424 is a classic, also Griot's Garage makes an excellent one (basically same specs as porter cable).
Wash your car, dry it, then clay bar it (plenty of tutorials online). Then use a LIGHT machine polish. This is the most basic chemical and physical abrasive, and the lightest of all the polishes. It's also the safest. But this isn't Meguair's Scratch-X or any of those (those are more serious).
Polish the entire car using the orbital. Clean it off and polish again if the marks aren't all the way gone.
Clean it off, apply a high quality sealant (not a wax, since you aren't a car nut waxing your car 4x a year a sealant lasts much longer), and call it day.
Cargeek.net has tons of great advice and good prices on all the products. Also look up OCdetails.com
If you need to buy all the products yourself, you are looking at a $250-300 investment in everything from a dedicated wash bucket, wash mitt, car wash soap, chamois for drying, clay bar kit & spray, random orbital buffer and polish, and a good sealant. It'll take you about 4 hours to do the whole truck with this process and it'll look showroom nice when you are done.
You can also pay a professional detailer ~$150-250 to do this and they should also clean out on the door jambs, detail the interior, and shine your engine, wheels, and tires as well. And it'll be good for ~6 months.
Joe