This is a fairly effective crossbow that shoots 15-20 feet with a rather fast velocity for its build.
To start you put two pencils next to each other. Then take the other pencil and center it in the middle of the other pencils.
Sorry for the distortion. Take the duct tape and cut it in half length wise and tape from the back to the front and back again on the opposite side.
Once again camera issues. But take the other half of the tape and tape diagonally over the two pencils to the bow part and back again. Then repeat on the other side.
Put the binder holder approximately half way down the two pencils. You can go farther if you like up the pencils but this usually causes failure earlier. Then tape the back pincher to the pencils very very thoroughly because this is probably the weakest link.
Then you put the rubber band across the single pencil on the edges. Then you pull the band back and place it inside the binder holder and your ready to fire. You can fire pens, pencils, special darts that I will post another Instructable on. Have Fun!