At the bottom back of the oil tank you'll find a hollow bolt w/rubber cap on it. Open the rubber cap, attach a hose to the bolt. Make that hose drain into a container. Open the bolt w/10mm or 12mm wrench (I forget which size). Let oil drain into container.
That is the hard way imo. I siphon the oil out of the tank w/clear tube. Or you can buy a siphon kit at the auto parts store. In any case the oil flows a lot better if it is warm. Make sure the screw in dipstick is out so you don't create a partial vacuum inside the tank.
I hope this helps.