Preparation:
Using the clear adhesive tape, attach a bit of the thread to the top of the pencil, to the metal part that is just under the eraser.
Hold the pencil in your hand, eraser side up. Run the other end of the thread to a button on your shirt or to a belt buckle. You'll need to anchor the other end of the thread on your body. If you choose to use a button, you can form a loop in the thread and wrap it around the button.
If you like, you can also tape the thread to your belt buckle. Of course, you're free to attach the end of thread in any manner that you wish.
You'll have to experiment a bit with the length. Basically, you'll want the thread to be fairly taut when you partially extend your arm in front of your body.
The next steps will make this more clear.
