Do this carefully because if you make a mistake, you should turn your paper over. Erasing will look messy. Now, before you add your stars, think. You need to decide how you want your stars to look. Chalk looks great on black paper but it does smear.
White toothpaste makes a nice, bright star but takes a long time to dry.
White paint is good if you can get some. Glitter on glue is always great.