Every person, employer, employment agency, labor union, real estate agency and rental office subject to this chapter shall post in a conspicuous place or places on his premises a notice to be prepared or approved by the commission, which shall set forth excerpts of this chapter and such other relevant information which the commission deems necessary to explain the chapter. Any employer, employment agency, real estate agency, rental office or labor union refusing to comply with the provisions of this section shall be guilty of a violation if a natural person, or guilty of a misdemeanor if any other person.