Not at all a fan of Guitar Hero. In fact, seeing as how I actually play guitar, my thoughts are that GH is to music was Tommy Wiseau's The Room is to cinema.
But I love the fck out of murals on guitars, even fake plastic pretend ones. Hell, if I knew how to do it properly, I'd splatter paint a phoenix onto my Squire. And I love the fck out of ponies. And I love it when two copacetic things that I adore are combined. So ultimately, this is a massive win.
This is actually a lot like what I did to decorate the CD for the copy of Come Clarity by In Flames that I bought for my youngest brother.
Any kind of marker will do, I used fabric markers. I started out by sketching out Vinyl Scratch and then I went over the sketch with the markers. For the rest of the guitar I kept the same color scheme used for Vinyl Scratch and I just alternated to colors.
I would say fallow some of the drawing guides over at Equestria Daily. That's what I did, my first pony that I drew before looking at anything looked all out of proportion and strange but after looking at a couple of them my ponies improved immensely. [link]
I still cant believe how much attention this thing is getting, also if anypony here is going to be at the NYC Brony Con this Saturday I will be there in artists ally with a shoe customization demonstration going on and all of my art will be there.