Just play the following over and over again for melody. Play around with it and have 
fun. These are also the chords used for Trans-Siberian Orchestra's Christmas Canon, just 
a bit of distortion.

for acoustic guitar play open chords


A2   E   F#m   C#   D   A2   E


or in power chords for electric guitar


A5   E5   F#5   C#5   D5   A5   E5

Have fun!