Step 1: Tinfoil.
Get your tinfoil cut it into a 4in by 4in square.
Step 2: Straws.
get your 4 drink straws then put them into each other so they connect it will make a cross shape.
Step 3: Cross and Tinfoil.
Tape your cross onto the tinfoil so that the tinfoil is in the middle of the cross.
Step 4: Birthday Candles.
Get the birthday candles and melt the bottom of the candle so there's wax then place the candle on the tinfoil, apply heat at the bottom of the tinfoil. let it dry
Step 5: Wax.
When the wax drys adjust the straw length to fit the bag, tape the straws to the inside of the bag.
Step 6: Lighting and Flying.
Carefully light the candles then wait and watch the balloon as it floats to the surface.