by putting it in the gas tank, it will run through the gas lines and into the carb, which should clean it out good.
For the crankcase, I believe it's 1 or 1.5 ounces per quart of oil (it says it on the bottle) and just pour it in with a funnel.
I've been using it since i got my quad in april and my oil stays nice and golden.
I haven't taken apart the carb, but it always starts up nice and quick and idles nicely, so i think the seafoam is working
AC Nerfs - Swingarm Skid + Honda Racing Skid - Protaper Contour Bars - Rox 2" Riser - CBR Clutch Perch - Oury Grips - HT Moto Seat Cover - Custom Poly Case Saver - TRX450R Front Shocks - XR250R CDI - YFZ 450 Dual Piston Front Calipers - ITP T9 Baja Rear + GBC X-Rex - CanAm DS450 Front Rims +Holeshot SR Front - Dominator Bumper - UNI Filter - 13/39 Gearing - DID x-ring Chain
AC Racing Nerfs - Oury Grips - Fmf Slip-on - Uni Filter - Razr Rears