Record a demo to provide to a prospective agent. Go into a professional studio and record your three best songs. Put your best song first on the playlist.
Email potential agents to ask them if they are interested in hearing your material. Find common ground by speaking about other artists each agent represents. Explain why you would be a good fit for the agency.
Send your material to potential agents who accept unsolicited material. Send your demo and a biography including any notable performances or accolades. Include a personal thank-you note.
Schedule a performance at a local venue and invite potential agents in your area via email or a phone call. Pick opening acts that will warm up the crowd and choose a venue that is appropriate in size for your overall popularity.
Build a local following. Make contact with your local radio station that plays music in a similar genre. Play high-profile shows in your town whenever possible and establish good relationships with local promoters.