Baking Soda (1 tbsp. or more it depends for how many nail you're going to treat)
Tooth paste
Citron / Lemon
Nail Brush
Procedure:
Mix the baking soda and citron or lemon.
Put tooth paste , baking soda with citron or lemon in nail brush
Brush it in all your nail inside and out, then leave it for 20 minutes then rinse.
Do these every night before going to sleep.
Do it regularly until your nail comes back to normal.