How to Tune an eight string ukulele
In this video, a man with an 8 string ukulele teaches you how to tune such a musical instrument, which is similar to tuning 4 strings of a guitar.
He starts be reminding you that the 12th fret of the ukulele must be exactly at the middle between the bridge and the nut. If not, the bridge must be moved to the correct position.
You must first tune the last string (the thickest) in G using another musical instrument or a tuning device. The next string is tuned by using the 5th fret on the G string, which gives you a C. The following one is tuned using the 4th fret on the C string, thus giving an E, and the remaining one is tuned using the 5th fret again, giving you an A. So the 4 strings (or pairs of strings) are G, C, E and A.
One important note is that the ukulele E string is tuned one octave higher than how it would normally be.
Since the ukulele has 8 strings instead of 4 (like a "double-six" guitar), the paired strings must be tuned to sound the same and in the same octave.