Using a headband to curl your hair will help you achieve bouncy barrel curls. This method is good for all lengths, given that you can wrap all the hair around the headband at least twice. Shorter hair may create tighter results, as well as some hair falling out of place during the night.
As shown in the diagram, you’ll want to start with a simple cloth headband. Not very tight. Brush your hair into place for where you want your hair parted off for the next day. Start by placing the band over the crown of your head until it is secure. Then, start taking small sections at the front working towards the back and wrap hair around the band until the ends are tucked. Once all your hair is tucked, loosen the hair a tiny bit by putting your fingers between the band and the tucked hair.
Next, to prevent a crease in your hair push the headband up as if you were taking it off, but keep all of the hair tucked, . It should feel pretty loose but still have the hair tucked in. If any small ends have fallen out don’t be alarmed. You can tuck them back in or leave all the ends out, if you want to create a more lived in look when finished. The looser everything is wrapped in the headband, the looser the final result will be. Wrap your hair in a silk scarf to prevent frizz while you sleep.