Not sure about your specific model, but for manual chokes in general you should adjust it so that when you push the *** in (off position) it should not go quite in all the way. You should have about 1/64 of an inch of space. This way you are making sure the choke will be all the way in the open position when running.
You should get no high idle when it is in the off position (*** in).
It is important to make sure it is opened (*** in) all the way when not needed (engine warmed up).
Sorry this sounds confusing. You might be able to look into the carb with the air cleaner off an see the correct motion of the choke.
2005 Sportsman 800 EFI Camo- Winch, Glacier II 60" Razor Plow, Brushguards, Rack Extensions "Sold"
2008 Ranger RZR Red- Deluxe brushguards, 3500lb Winch, Fender flare Kit, Nerf bars, Cargo box, Hood scoop, Sport Roof, Aluminum Rims
2009 Sportsman XP850 EPS Camo- Winch, Lock and Ride frt Cargo Box, Rack Extension, Deluxe Brushguards, 27" Mudlite XTR's 66" Polaris Glacier III Poly Blow
2010 Sportsman XP550 Green - Rear Polaris lock and ride cargo box, Warn XT25 Winch