#1
What type of media can I use for customizing? Would it be acceptable to use colored pencils on a sanded guitar? If not what type of paints can I use? I will be customizing an acoustic guitar. Any tips are GREATLY appreciated!
#2
you can use what ever you want. Some things will produce a better overall product.if you sand it down, try some good paint pens/markers. I'd go for the Acrylic pens over the Enamel though. seal it with a few coats of min-wax acrylic Lacquer clear to protect it
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#3
I agree with Robbsgnarly that is how this is done. One guy on my craigslist had this piece of crap guitar and he stripped the finish and put what is equivelant to in America of monopoly money under the finish... not gonna lie I kind of wanted to buy it but 100$ was a little steep for a no name. Once the lacquer / polyurethane has cured you're good to go.

this is a fantastic example of what can be done
https://www.youtube.com/watch?v=HMSvhuPLmSU