I just act like as much of an @$$ as they are. If they walk down 20 feet I walk right up next to them. Cast out cross their line etc. If they ask why I'm crowding them I reply, "hey I was just gonna ask you that!" They usually get discouraged and move on, you gotta be territorial. Dirty looks don't hurt either.
Here in westport, we have this guy who guides, (not mentioning names in case he belongs to this site

) But if you are into fish he will buzz right up in his boat and practically tie off to your leg. If you complain he says "hey, I got a charter here"
"Hey if you call yourself a
GUIDE you should have no trouble finding your own fish, especially in a boat! Most of us have thrown rocks at him at least once. Sometimes I'll empty a bag of chips into the water and reel a popper under the surface, when nothings doing. Rod doubled birds everywhere, here he comes!!! Tip the cap and smile... off he goes
-DAve