I have an epi Black Beauty and i love it. What would you use to clean the fretboard and how would you do it?
Go buy some lemon oil and some new strings
Take off old strings
Apply lemon oil sparingly to the first fret
Use an old tooth brush and scrub the fretboard
Wipe down the fret with something dry (Napkin, dry cloth)
Apply lemon oil to the second fret and repeat steps.
do the rest of the frets like that
Put on new strings and play!

You can get the right lemon oil at any ol' guitar store and it works perfectly for me.
For those who care.
Current Gear
Cort Zenox Z42
Flextone II
Charvel USA So-Cal
Farida M2 Parlour Acoustic
Admira Hand-built Spanish Acoustic
Blackstar HT-5H
Line 6 M13