Require that the potential artist audition. Many new artists attempt to enter the rap community, only to fail in gaining popularity. A promoter believes in his artist. Prior to agreeing to promote him, ask that he perform for you. Also, ask that he write his own work. Merely reciting another's composition does not require the same talent as composing your own.
Once you establish the talent and writing skills of the rapper, introduce him to the public. A rapper generally does not require a large stage, needing only a microphone and turntable. Print flyers, advertise in local newspapers, and request radio interviews. Meet with radio personalities prior to the performance. This provides immediate contact with the audience, as well as show promotion. When managing a new artist, seek methods of audience-building.
Create a mix tape. Record the artist live, in a number of venues once he composes enough solid material. The mix tape serves as a rapper's primary source of publicity, and can help him to receive large-scale attention. Distribute the tape, but give away a few of the first samples as well, as not all potential audience members pay for an unestablished artist. Free, word-of-mouth publicity serves the artist.
Hold a showcase. Industry members continually seek out new talent, and in the rap community, established artists maintain their relevance and crispness by collaborating with new talent. Decide the rapping style of the artist prior to distributing his mix tape to industry members, as they only attend if his method of rapping fits their vision.
Piggyback an established artist. Request that an established label mate support your artist's exposure once he receives solid interest from a label, and a contract. Though his contribution may be minor, possibly consisting of a few lines, if the delivery offers something unique, his popularity will grow. He promotes his own work in this method, and a new audience will partially come from that of the established artist.