Hi, How you doing? Justin here, today I'm going to show you- how to get you guitar into Double Drop D tuning little bit- more common on the acoustic guitar, but works on electric guitar great as well, very very simple tuning again, double drop D means that we are tuning the two outside strings- the 1st string and the 6th string down to a D, they are normally at E, so, both strings are gonna go down 1 tone, now to do that we're gonna play the open 4th string and play the 6th string and tune it down until its an octave lower okay? now, if you're struggling or you wanna get a little bit more accurate you can use the 12th fret of the thickest string will put that string up an octave so its the same as the open 4th string its a little easier to hear okay, now we're gonna tune the thinnest string down a tone as well, so we do that again, open 4th string gradually tuned down as usual we try and tune up to a note, so now just tune down to it tune a little bit lower than you know that it should be back up again you can use an octave at the 12th fret of the fourth string that's pretty good, Okay now, nearly every time you do an open tuning you get a need to play a little bit and do a little bit tweaky, its just a part of the way it is so, what you wanna do for a double drop D is play regular D chord, lift-off your second finger here we go just had turn up that thinnest string up just a tiny bit there you have it that would be a double drop D tuning, very common in acoustic stuff, really really nice its kind of common one for the fingerstyle and percussive guitar and all that sort of stuff I hope you really enjoy whatever song it is that you're going to learn using double drop D take care!!