I always acquire ebay or forum members cast-offs and follow this procedure:
Remove existing bat face very carefully
Remove any residue
Sand the whole bat back to the natural wood and fine sanding until i'm happy.
Rub on with cloth a generous layer of salix bat wax all over except splice area and leave horizontal for a day or two until it's 'soaked' in and dry to touch
Knock in with a hardwood bat mallet for several hours until i'm happy with the middle and edges
Finish with a ball mallet
Add a final thin coat of bat wax, leave to dry and add a 'hammer edge' bat face sheet
Finally the nets to determine if further knocking in is required
I love it unlike some members but that's just me.. I like knowing my bats have been finally match prepared by me, but then I'm an opening batsman too so maybe that has something to do with it...Also i've never sent a bat off to be serviced either...