protect yourself: mask n95, goggles, gloves, clothing.
 prevention: what's causing the mold? Where's the moisture coming from?  removing the mold: what kind of wall? Different wall types like wallpaper, plaster, wood need different removal than hard surfaces like hard plastic, glass, metal.  disinfect. More info found here: http://www.Ag.Ndsu.Edu/pubs/yf/home/ae1202w.Htm.