Have you ever watched somebody in class or at the office skillfully twirl a pencil around his or her thumb and wondered how that person did it? Have you tried to do it on your own and found that it's not as easy as it looks? By following these steps and practicing - a lot - you can amaze curious onlookers with your brilliant pencil spinning, too!

[edit] Steps

The starting stance

Hold the pencil between your index, middle finger, and thumb. Your index and middle finger should be spaced about the width of your thumb apart (Your thumb should be able to fit between your index and middle fingers). Your fingers should point upwards about 20-45 degrees. Your middle finger should be against the center of gravity of the pencil (towards the middle, slightly closer to the eraser).
Mid-twist

Simultaneously fold your middle finger in (at the joint closest to your hand) and extend your index finger. Your middle finger should end up resting with the inside of its last joint on the thumb.
The catch

Catch the pencil after it wraps around your thumb and hits your middle finger, by moving your index finger back to its original position.
Practice this by holding the pencil in your non-dominant hand and guiding it around, so that you get a feel for how it should move. Also, the angle to hold your hand at varies from person to person. Experiment to find your preferred angle.If you still don't understand how it works, watch this video, and you will know how to do it better: How to Spin a Pen Around Your Thumb

[edit] Tips

Folding the middle finger should cause the pencil to "roll" off of it. It is not a flick. If the pencil flies off without touching the back of your thumb, you're flicking it.
It helps to think of the push as rolling AROUND your thumb, at the base.
After you start the push, try moving your thumb in a manner that there is more space between your thumb and hand. This creates a larger area for the pen to fall into.
The pencil should make constant contact with the skin between your thumb's nail and joint. If it touches the joint you aren't folding your middle finger fast enough, if it touches the nail you're holding the pencil incorrectly (it should start at the center of the thumb, with the bottom of the pencil at the bottom of the nail. It will lose some height as it spins).
When the pencil/pen spins the balance point of the pencil should be in the middle of your thumb
Don't move your hand or thumb at all while doing this.
If using an imbalanced pen, hold it at the heavy end.
Once you've gotten good at spinning the pencil around your thumb, you can try spinning it back the other way! This will return the pencil back to its original starting position. Refer to here for instructions.
If you have a tough time getting the hang of it, try to make sure your thumb is flat. This is what the pen is spinning on after all. You don't want the angle of your thumb to send the pen rolling somewhere else.
This is not a beginner's trick! It is very hard, so do not do this if you don't know how to levitate yet.

[edit] Warnings

When folding your middle finger back, don't push too hard. It barely takes any force to send the pencil all the way around.
Practice this only when you have something for it to land on. Do not do this while sitting at a school desk until you get good, as it will more than likely fall on the floor every time. You can catch the pencil in a coat or jacket on your desk, though.
Remember to replace the cap or retract the point of a pen before you try to spin one. Not doing so may result in stains and embarrassment.
Be careful not to hit your eyes or anybody else's eyes.
A pencil with no lead is better when beginning, you may stab your hand...(it hurts!)

[edit] Things You'll Need

Pens or pencils. Unsharpened pencils are the best because they are long, moderately heavy, and perfectly balanced. Some fanatics even take to customizing pens to get them just right.
Try using a drumstick. Its weight is such that it becomes hard to spin it too fast. Hold it close to the center.

[edit] Related wikiHows

[edit] Sources and Citations

Iluvitar's tutorial Includes some good pictures and advanced tricks.
Pentrix Has videos and tutorial articles.
Pencil Ninja One of David Weis' sites (the master of pencil spinning) with videos of him performing.
Super Handz Features links to other sites and some crazy videos. Also has information on the other "hand sportz," card manipulation and cup stacking.
Pen spinning - Wikipedia Some history, information, and other techniques of the art.