You will need
16mm FOE Elastic and the following lengths depending on your size.
1. NB-4mths 12″-30cm
2. 4mts-12mths 15″-38cm
3. 12mths-3yrs 16″-40cm
4. 3yrs to adult 18″-46cm
Cut your fold over elastic to length and heat seal your ends with a lighter or candle.
Overlap your ends about 1cm and sew together you can machine or hand sew.
I machine sew with a zig zag stitch.
Take a small lenght of FOE elastic to make a interchangable headband. Seal the ends. Put a dab of hot glue on the back of the headband and glue the sealed end.
Rap strip around the headband so it sits flat and cut it to length and seal the end and put a dap of hot glue on the back and glue down.
You now have a interchangable headband. You can add a flower, or ribbon hair bow.