Mold often grows in wet places and cause health problems. These places usually has leakage or water damage. This is why it's important to fix these problems. Here's a procedure of one of the ways to get rid of black mold:
1) Take a bucket with warm water, and add 2 tablespoons of liquid dish soap. Dip a bristled brush into the soapy water and scrub the moldy surface with the brush. Repeat it until the area is cleaned.
2) Add an equal proportion of water and ammonia and pour this solution into a spray bottle. Spray the solution evenly on contaminated areas. Let it sit for 5-10 min. Use a brush if necessary, otherwise wipe it clean. Give more suggestions if you have any.