OK. Here's the things you'll need to mount a Unicycle:
1. Unicycle
2. Feet
3. Arms
4. Torso
5. Legs
o_O' Seems to me, most should have the requirements except for a Unicycle. Try this
site for buying uni's.
Now. Here's how to mount:
1. Place the Uni in front of you with the peddle on your DOMINANT side roughly 90°.
2. Push down on the peddle on your DOMINANT side and lift your body up.
3. Sit down on the seat.
4. Put your other foot on the other peddle.
5. Lean forward and even the peddles.
6. Idle or ride forward.
That's all there is to it.
Now, if you are just starting, you'll not get it down so easily. What I suggest is either riding along a wall that has a railing to hold onto OR having two people at your sides and sling your arms around their shoulders for support.
Have a good one.