Let's talk about E flat tuning. This is a little tricky to do. A lot of groups tune to E flat in order to match the singer's voice a little bit. I can think of Jimi Hendrix, Stevie Ray Vaughn, Eddie Van Halen: they like to tune to E flat a lot.
This is what I'm doing: I'm bringing E, A ,D, G, B, E, and I'm going to flatten all of them. E flat, A flat, D flat, G flat, B flat, E flat. What I'm going to do here is find E flat, and I'm going to tune my sixth string to E flat. I'm going to go to the fifth string, and I'm going to go to the sixth fret, and I'm going to try and match that. I have to come down to flatten.
So I matched that pretty good. Now, from there, I can just use my relative tuning. My sixth string is the note that I want it to be, and I can go ahead and tune the rest of the strings with that.
I'm going to go to the fifth fret of the sixth string to tune my fifth string. Once that's in tune, I can go ahead and do the same thing with the next one.
And then once that's in tune, I can go ahead and do the next one, back at the fifth fret still.
This is that third string where I have to go to the fourth fret.
And then the last one, back up to the fifth fret.
Now, the thing about loosening the strings, is sometimes they take a little bit to settle in. You might find that when you play your chord it's a little bit out of tune, but if that's the case you just fine tune and go back through the same process and make sure that every one of them is in tune.
And there you go. E flat tuning.