Here is a way to dewrinkle ribbon using a hair flat iron. Just pull the ribbon as you iron. I use my foot to hold the ribbon down. Use a water spray bottle if wrinkles are tough.
Ironing Ribbons
Using a Flat Iron
Keeping Jeans from Getting Wrinkled in the Dryer
How to Make a Candy Bouquet
Why Are My Clothes Wrinkled After Washing?
Cleaning a Curling Iron
Making Melted Bead Suncatchers