I find the idea with the PET lanterns very nice, too, and it should be relatively safe with the Christmas tree candle holders inside :)
I made a short translation:
“Materials:
PET bottles, Christmas tree candle holders, wire, Wico colours*, candle
Instructions:
Cut open a big PET bottle (transparent or coloured) about one third from the bottom.
Colour with Wico colours*.
insert a Christmas tree candle holder into the bottle top. You must take apart the little candle holder and attach it with wire to the bottle top.
Prick two little holes into the bottle neck (e.g. with a hot knitting needle).
You can embellish the top cut with pinking scissors or a metal band.
Prick three little holes into the top edge (e.g. with a hot knitting needle) and attach three wires or fine chains of equal length to hang the lantern up.”
* Wico colours is Window Colours. These are those glass paints that come in plastic bottles and can be used on acetate sheets, I don’t know the exact English name.