I've been successful at removing squeeze-out by tackling it as soon as I have the clamps set. I skim off as much as I can with a putty knife, and then use a very wet rag (I keep a jar of water handy) to wipe squeeze-out areas very thoroughly. The glue is water soluble and if you use enough water you can get it all off. The wood gets quite wet and after I'm sure I've got all of the glue off, I dry it with a rag.
I've tried the method of letting the glue get "somewhat dry but not hard" and it's been more of a nuisance and less successful because I frequently run into wet glue under a skimmed over area.
Any comments or suggestions?