You don't need a buffer to polish a guitar to a dazzling gloss. You can do it by hand with rubbing and polishing compounds. It's easier to buff a guitar by hand because you don't need to remove most of the hardware, and your fingers fit into the small places that are cumbersome for machine buffing. Special buffing compounds are gentle on your instrument and give it what it needs to shine without machines.
Remove the strings from the guitar. Remove the pickgaurd, if applicable, with a screwdriver.
Squirt a quarter-sized amount of rubbing compound onto the guitar. Rub the compound around in circles with a damp cotton cloth. Rub the entire guitar body in small overlapping areas, adding more compound as needed until the guitar has a smooth, cloudy look to it. Wipe the guitar clean with a dry cloth.
Repeat rubbing down the guitar with the polishing compound in the same manner as the rubbing compound. Work in small overlapping circles until the guitar body is covered.
Wipe the guitar body with clean with soft, dry cloth. Hold the guitar up to the light. If the guitar does not reflect light, continue rubbing it with polishing compound until you can see your reflection in the lacquer.
Replace the pickgaurd and strings.
You can order guitar rubbing and polishing compounds from online guitar catalogues or buy auto body products that work just as well at a local auto parts store.
Do not polish or buff the guitar neck; it's not necessary and may have an adverse affect on the fingerboard.