1) Is a potentiometer the thing you put the knob on and use to change volume/tone?

2) Am I right in thinking that the best way to paint a guitar is to spray it?

Rockin' shit
Yep the pots are the volume and tone controls.

Spray is easiest way to get a smooth gloss finish. But you could use polyurethane paint and build up enough coats to be able to wet sand it smooth, then polish it glossy.

Or you can take the guitar down to bare wood, stain it (they do have colored stains) and the coat it with clear, glossy polyurethane.

I suggest the polyurethane because it provides a very hard surface that resists scratches, cracking and discoloration.
spraying is quite complicated. head over to building and customising for some sound advice
Get off this damn forum and play your damn guitar.
Unless you know EXACTLY what you're doing, painting a guitar is a great way to screw it up.

Guitar bodies are made out of special woods called "tone woods", which as the name suggests are types of wood with a specific density that allows vibrations to resonate especially well.

The finishes on guitars (especially acoustic and hollow body) are a specific paint applied to a specific thickness, usually around the tenths of millimeters, so they don't interfere with the wood's resonance.

Unless you feel comfortable dealing in such small increments, or unless you have a guitar you really don't care about having to replace, I'd highly advise against painting it yourself.
-Guitar Gear-
1995 American Fender Strat, EMG 85 pup
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