tune your A string to the 4th fret on the E, then tune normally, including the E string after you've tuned the A....
Washburn WI66 Pro E Celtic Cross (1 of 48!)
Washburn WI66 Pro Honeyburst
Takamine EG334SC Acoustic-Electric
Peavey XXX 120W All Tube Half Stack
Line6 MM4/FM4/DL4
Boss NS2
Vox Snakecharmer Compressor
Digitech XP100 Whammy Wah
A simple trick for if you have a tuning device:
hold your finger on the 1st fret of every string and tune your guitar to standard tuning like that. Or use a capo on 1st fret, is just the same.