Leave the battery connected to damp out any possibility of spurious charges.
I agree on disconnecting shore power it eliminate any possibility of welding currents getting into the house's power system.
Other than that, the usual:
Make sure your work clamp has a good clean contact area
Cleaned all paint, rust, etc. from the parts to be welded
Protect any surfaces from sparks and hot slag
TT 2015 19RD "TheJayco"
TV 2003 F-350 "Montblanc" - Housebroken chore truck
Sitting in The Cheap Seats.
And proud of it!