This is SO much fun!
Decorate with ribbons and pretty stuff (not so much so as to weigh it down).
Attach a shortish length of string to each side of the open end of the bin bag (long enough so the bin bag can open out and fill with wind).
Then attach a long piece of string (as long as you want to let it out!) to the middle of this string.
Great fun, great for bonding.
“What if people think we are silly?”
*Nobody thought we were silly, they flew really well. Will be doing again one windy day!