A Little Nightcap
Here’s a slumber cap that will stay put as you sleep. Make it small for a cute bun net or make it large to fit tons of curly hair. If you need it extra, extra large, use a needle one size larger than those specified in pattern (ie: if a section calls for a US 5, use a US 6 instead).
Here’s a link to the type of headband used in the slumber cap. Any brand will do as long as it’s about 0.5cm wide and has no metal.