If you iron over a square of cotton with bees wax, than you get the environmentally friendly version of plastic wrap which you can reuse as you like! 🙂
On YouTube there are a lot of tutorials which also show different methods (iron // oven):
→ YouTube-Tutorial (iron)
Alternative to bees wax you can use carnauba wax which is not made of animal products.
There’s a tutorial here (german):