How the heck do you play behind your head? lol just always wanted to know..
is there like a technique to doing it or what?
There's no special technique. Eventually you learn to feel where you are, so you don't have to look at the fretboard when you're playing. That way, you can hold the guitar anywhere and play. The thing is, because your arm is bent, it's uncomfortable to reach certain frets, but it's easy around the 10th to 15th fret region.

I tried and managed "sweet child o' mine". I know it's not the ultimate behind-your-head song, but it works.
The thing with rock bands are that they practice the **** out of what they play, so playing their own songs at a show becomes second nature. When you have something THAT memorized, it's not very hard to use other tricks and techniques to play it, since you're so rehearsed. That's what I think, at least.
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Sailor Jerry
Heh, it's not terribly hard really, just mess around with it behind your head and get used to the "backwards" orienation of things. It usually helps to have it resting on your back/shoulder. Work with a riff or scale you know well before going to pure shredding and wanking behind your head.
"We are what we pretend to be...so we must be careful what we pretend to be."
Nice quote, FakePlasticMan
...And you said the Holocaust would never happen. Ha, you lost your bet, Jesus!
its not hard. Just know your guitar. It's hard to do on a new guitar...
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