How to tune a 12 string guitar

The modern twelve string guitar appeared in The United States at the end of the nineteenth century. Nobody knows who first got the idea of making a guitar with double courses of strings. Some guitar historians see the twelve string as an extension of the long tradition of coursed instruments in Italian musical history. But many people think that Mexico, with its tradition of variations on the conventional guitar is the more likely source.
A six string guitar has 6 strings tuned to E A D G B E. The twelve string guitar has six pairs of strings, each pair tuned to the same note but E A D G are tuned an octave apart. B and E are in unison.
To start tuning a 12-string guitar, let’s look at the strings:
E (First String)
e

B
b

G
g

D
d Tuned to the 2nd string - 3rd fret

A
a Tuned to the 3rd string - 2nd fret

E
e (Sixth String)Tuned to the 4th string - 2nd fret

So use your guitar tuner or pitch pipe to get six of the strings in tune as normal. Then go back and do your additional 1st, 2nd and 3rd strings as normal. Then tune your additional 6th, 5th and 4th strings an octave higher.
I’m afraid the final step is to go back again and repeat the tuning process a number of times until your guitar is in tune because the neck of a twelve string guitar comes under alot of stress, and the pithch of the strings will change!
It’s harder to explain than it is to do, so after you’ve done it once, it’ll be a snap!
Once you have got the hang of it, there’s a neat trick for playing twelve string guitar: removing the higher octave from the E A and D strings makes playing running bass lines easier, without losing that distinctive twelve string sound in strumming passages.
The twelve string guitar is great for strumming along accompanying songs but it does not lend itself to the techniques involved in playing lead guitar.
The twelve string guitar has a warm, ear-friendly sound which draws attention to the guitar even behind a group of singers.
Twelve string guitars are usually acoustic, although some lead guitarists have used electric twelve string guitars from time to time.
Guitarists who favored the twelve string include early blues guitarists Blind Willie McTell and Lead Belly, folk singer Bob Gibson and sixties folk-rock innovators, The Byrds. It has not had any great popularity since the seventies when Led Zeppelin and The Eagles recorded ‘Stairway to Heaven’ and ‘Hotel California’.

Leo Kottke plays 12 string guitar
He may not be everyone’s cup of tea, but Leo Kottke made a name for himself in the 19070’s with his unique self-taught 12-string guitar style.