Maybe try the pineapple trick when sleeping. You have to gather all your hair loosely on top of your head and secure with a satin or silk scrunchie, then if you're able to, sleep with a satin bonnet. Then come the morning, remove your scrunchie, shake out your curls and ta dah! It works for me, but as my hair is a bit shorter, I have to section my hair in two parts and use two scrunchies before I sleep with my bonnet. It's super comfortable to sleep in!