Wake up with less frizz by minimising overnight friction. Cotton pillowcases...

https://mill-wiki.win/index.php/The_Beauty_Editor%E2%80%99s_Guide:_How_to_Create_a_Sleep_Environment_That_Supports_Hair_and_Skin

Wake up with less frizz by minimising overnight friction. Cotton pillowcases are often rough on hair; switching to silk helps retain moisture. For extra protection, secure your hair in a loose, comfortable style before bed to keep it smooth until morning.