Barber Hone advice

[baldy]

This hone just arrived in the mail today (ebay $20 U.S.) and I must say I'm pretty pleased, while the box is a little beat up the hone appears to have never been used.
All I know about barber hones is what I've read on the wiki so I wanted to check 2 things with you guru's
1) I think I'll give it a lap before use so is something like 320 grit w/d the way to go on something like this?
2) I assume I can use water or lather on this, is either method better than the other and once you choose do you have to stick to that method, or can you change between the two?
Thanks