I really want to learn Andy Mckee songs. The problem is that its way too complicated for me. I play mostly electric guitar(I can play metal very well, sweep, tremelo,etc.) but I'm not that great at acoustic.

What techniques should I learn and how should I go about learning them?

The song I really want to learn is Rylynn: http://www.youtube.com/watch?v=JsD6uEZsIsU

Thanks in advance.
you want to be familiar with the acoustic guitar before you even touch Andy McKee's music
Lol, what a great question.

For starters, you need to have AT LEAST, 8 months of acoustic practice. Meaning, being extremely comfortable with every aspect of acoustic, were not talking about playing 4-chord songs, and strumming the entire time. You need to be a good fingerpicker, no question about it. That's about 65% of it. The other 35% will be percussion, harmonics and tapping.

Percussion will be somewhat difficult in the beginning, but as soon as you get it down, it becomes entirely natural, and is applicable to any song that has it. Not to mention I sometimes add it to songs that didn't have it to begin with, usually, songs just sound better with it.

Harmonics work the same way as they do on an electric, except it will take more skill to execute them well on an acoustic. And there are many, many different ways to perform them as well.

Tapping, will be the hard part. You have to use much more force to make the notes sound on an acoustic, and even then, you need a good guitar so you don't get those ugly undertones. This is the hardest for me, because the majority of tapping in Mckee's, Dufour's or other artists of the like, are not synchronized with the other hand, like playing piano. And I have a really hard time trying to get both hands to do separate things.

A really good sing to teach you the basics of fingerpicking is Classical gas by Mason Williams. There's tabs on here, and I highly recommend you learn the piece if you have any intention on learning acoustic let alone Andy Mckee.

That's basically all the technical aspects of it, easier said than done, for sure. But when you learn these well enough you should be on your way to being able to play those kind of songs.
also, a good knowledge of using open tuning will help, so that if you want to construct you're own songs in that style, you have an idea as to what works.

as for the playing, romeo pretty much nailed it
To get used to moving a bass line and a lead simultaneously in unrelated directions, start with Bach's "Bouree in E Minor", then try "Classical Gas", which has already been suggested. Then, to get used to percussion and tapping, a good semi-easy song to start with is Mr. McKee's "Drifting". Then, to get used to heavy usage of harmonics, try "Ebon Coast". Once you've got all that mastered, you should be able to play "Rylynn" no problem.
I'd recommend learning 'Drifting' first that isn't too difficult, neither is the first part of 'Rylynn' really, if you can finger pick this is, if you can't then learn 'street spirit by radiohead'.
Just try learning them slowly, getting each part right, shouldn't be too hard to get it sounding alright once you get the timings together
Guhh, I dont have any advice, but I just wanted to say, I love Andy McKee and Antoine Dufour, simply amazing.
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