Start by cutting off about a four-inch piece of green duct tape. Roll the duct tape around the pen, this is your stem. Take your roll of duct tape and cut off a two-inch piece.
Turn the strip so the long end faces up.
Take one corner and fold it in toward the middle, so there should be a strip on two sides.
Fold the thin strip over, making a triangle with one strip at the bottom.
Wrap tightly around the top of the pen. Alternate the petals so they are at the same length the whole time. Continue this pattern around the pen.
Once you have the desired amount of petals, you can finish off by adding green petals around the base of the pen to look like leaves. After this point, you're finished!