What is the best way to clean a computer motherboard without damaging it? Is there some kind of a volatile solvent that comes in a spray can that would work? Would brake cleaner work? Rubbing alcohol and a cottonball?
Follow the advice in cleaning water soaked electronics in this section of the Repair FAQ. Don’t try to cheap out on cleaning solutions. Use plain Isopropyl alchohol, not rubbing alchohol, etc. Try to get some “zero residue” cleaner from an electronic supply store. (Yellow pages!)
If you can’t clean it right away, take out the batteries and anything else removable that’s not tainted, wrap in air tight bag and store in a freezer until you can work on it.
You will need lots and lots of swabs, tiny brushes, etc.