All you need is
and a party popper
Step 1: The Popper
first get your popper and get your scissors and jab a hole in the top and pull the top out.
second get rid of the confetti
third cut down the edge to get rid of another peice of cardboard
now you should be able to see the ignition so slowly pull that out.
Step 2: The Envelope
now you can open the envelope and tape the ignition on the bottom of it.
then get your card and tape the string on it (so when the card is pulled BAMMMMMMMMMMMMMMMM!!!!!!!)
lastly tape the envelope tape or glue it back together!