The best baby bedding sets are made with 100% cotton fabrics that are safe for your child. Get at least 2 sets: one for the day and one for the night. Your baby needs a set that includes: 1 fitted sheet, 1 top sheet (a roomy flat sheet), and 2 pillow cases (this is especially important if your child uses a crib or toddler bed). You also want to make sure there are no corner posts on the crib.