To reshape the curve of the nail, always file in the same direction using the black side, going from the side of nail toward the center to avoid peeling. To maintain the curve of the nail, file with the white side.

Beauty tip: 5 steps to gorgeous nails
1-After removing remnants of nail polish, submerge hands in warm soapy water for several minutes in order to soften the cuticles.
2-Dry your hands and push back your cuticles with the small cuticle pushers. This will leave your nail borders clean and uniform.
3-Polish your nails to make them smooth and shiny.
4-File your nails, always in the same direction to prevent layers from peeling.
5-Massage a moisturizing lotion into nails and cuticles or apply nail polish.