E - A - D - G are tuned via 5th fret and 7th fret harmonics.
Place your index finger on the E string just touching the string right above the 5th fret but not pressing down on it. Place your ring finger on the 7th fret of the A string doing the same, just lightly touching it but not exerting pressure. Hit the E and A strings with a pick and you should get a higher picthed tone, the two similar to the two notes from Jeremy by pearl jam...you'll know what I mean if you do it right.
The two notes are the same. If they're in tune, and you have any type of ear at all, they'll be spot on. Anything off at all will make the notes modulate. Adjust the out of tune string until you have one steady note with no modulation, or as close as you can get. Repeat this for the top 4 strings, E - A - D - G
for B you hit the harmonic on the E string 7th fret and just pick an open B
For high E you hit the harmonic on the A string 7th fret and just pick an open high E
