The curls in 4B hair zig-zag.
For a natural crown a popular technique for defining and accentuating your curls is twisting into shape. Try using something with a resin or gel base like BODY.BUILDER or HAIR.RESORT to give you the ability to mould and create hold while reducing natural frizz.
Treatments are key here, you can even leave them in to dry. Use a highly moisturising masque like YOUNG.AGAIN.MASQUE, add the product and twist the curls around your fingers. Do not disturb as it dries and if you need more moisture use YOUNG.AGAIN DRY CONDITIONER to help reduce frizz.