I no longer have a tuner. My ear automatically knows what 440 Hz is. I tune the A string to that, then the rest of the strings to it. Ring the natural harmonics at the lower string at the fith fret, and at the seventh fret for the higher pitch string. They should be in the same pitch. Do this for all the strings, except for the G and B strings. On the G string, ring the natural harmonic at the ninth fret, and at the fith fret for the B string. They should be in the same pitch.
EDIT: I forgot, the A string is tuned to 440, and not the low E. Sorry for the confusion. But, you can tune the low E to the A with no problem.