It's quite simple, really, but for you not to get dizzy and stop where you want to stop, it takes practice. Put your sword away for now, That part comes later. The basic motion is to spin on one or both feet (after a while you get used to spinning on one foot) and control your spinning, so you shouldn't get dizzy, and then stop where u want to by placing your foot (or feet) down.
Watch.
*I balance myself on the tip of my left foot, and then with utmost focus, I spin on it and I don't get dizzy. After a few seconds of spinning, I place my foot down, and stop spinning at the direction that I wish to stop at.* See? Try it.
While I'm at it, you shouldn't trip yourself either when you stop spinning lol.