Depends. Best method is to remove the tank, drain it as best you can, then put the whole tank smewhere warm to evaporate whatever is left.
If you can't remove the tank, drain what you can, then use tissue to soak up the residue. On Brissg engines, thats probably all you need to do.
If the engine has a bowl-type carb, drain that, too.
phil_saunders(a)bigfoot.com
Phil Saunders
April 2010