What should be done to nails before a manicure to ensure cleanliness?

Soaking the nails in warm water before a manicure serves several important purposes that contribute to cleanliness and overall nail care. Warm water helps to soften the skin and cuticles, making it easier to clean the area effectively. This softening process allows for better removal of any debris or dirt that may be trapped around the nails and cuticles. Additionally, soaking can help to hydrate the nails, promoting a healthier appearance and preparing them for any further treatment or polish application.

The other choices do not directly contribute to cleanliness in the same way. Painting nails in a light color does not cleanse them; rather, it simply adds color. Applying moisturizer is more about hydration rather than cleanliness, and using an abrasive file is intended for shaping the nails rather than cleaning them. Therefore, soaking nails is the best practice for ensuring readiness and cleanliness prior to a manicure.