Just watching the goegous Olympics Closing Ceremonies-those single-wheel cycles are neat-any idea how they are to ride? How do you steer those things?
Assuming they’re just unicycles (I didn’t see the ceremonies, so I don’t know if they were some special sort of “Chinese” unicycles), googling “how to ride a unicycle” gets you to a site like this. There are others.
ETA: the same search string turns up a number of “how to” Youtube videos.
For the record, I believe this is what the OP was referring to. It’s picture 5 of 66, if the direct link does not work.
Actually, such things are called “monowheels” or "monocycles.’
I’ve seen things like that in parades. It looked like you steer just by leaning.
I was really surprised they could get consistent enough results out of them to use them in the ceremony. It seems like the kind of vehicle where you either fall over or crash into someone half the time.
Burning Man! 
No, the real danger of a monowheel is called gerbilling.
I had seen these in a Capri Sun commercial of all places, and asked about them here a while back. Per one of the responses I received:
Without even searching I can visualize that effect perfectly 
Imagine a coin doing it’s wobble as it falls over after spinning.
Just stay away from Richard Gere.
my husband and i started cracking up when we saw that. anybody remember the episode of south park where mr/mrs garrison was riding a similar vehicle that he propelled by sucking on an object in the front and having an object likewise inserted on the opposite side of his body???
Youtube video of Monowheel Crash
That looks fairly painful.
Yeah but it beats the airlines.
No, no, not that - imagine a gerbil that runs too fast in its exercise wheel, so that it starts spinning around inside rather than running on the spot. That is gerbilling.