An empty sealed envelope open with scissors on both sides. Paste narrow leaf of colored paper. It should appear on the left and on the right side. Now the envelope is cut together with the paper from the bottom up into two equal portions. Again show the piece - it was intact!
Reveal the secret of focus. The envelope is pre-cut in two places, as shown in the figure.
On the opposite side that is not visible. Through these holes and is inserted colored paper. Her middle part remains outside.
When cutting scissors will be held between the envelope and the sheet. So it will remain intact. Showing the focus, keep the envelope slots to himself.