Hang a curtain rod draped with sheer curtains (or fabric) at headboard height, behind the bed, then add some white holiday lights behind the fabric and across the rod.--- maybe just a string of lights over the headboard :)
This would also be a cute dorm room idea. Also good for a gift for a girl leaving for college: package a set of fairy lights, clothspins, and small command adhesive hooks. Print this picture to include as a guide.
Instant Picture Hanging Kit (New color options!) - Standard Beige 3
DIY Dorm Room Decor Ideas - Dixie Cup Garland - Cheap DIY Dorm Decor Projects for College Rooms - Cool Crafts, Wall Art, Easy Organization for Girls - Fun DYI Tutorials for Teens and College Students diyprojectsfortee.
30 DIY Small Apartment Decorating Ideas on a Budget