Build a website for your concert series. The website doesn't need to be complicated, but you should include a schedule of events, links to individual artists' websites, and cost information. If you have sponsors for the event who provide food and drinks, include links to their sites for goodwill. Update the site regularly and include photos. Consider publishing a page about living room concert etiquette to help newcomers know what to expect.
Advertise on classical or public radio stations to reach people who are interested in concert music. Many living room concerts use classical, jazz or folk music because it will not be too loud. Choose simple, short notices that give the day, time, and a website to visit for more information. If possible, arrange to have the ads play in the morning and early evening when people are in their cars on the way to and from work.
Create profiles on Facebook and Twitter that are dedicated to promoting artists and the concert schedule. With these sites, you can reach a wide range of people who have expressed interest in concerts. This helps you avoid wasting time and effort. Invite past guests, friends and family to become your friends or followers and publish posts about upcoming concerts. Add details about the musicians so potential audience members can connect with them and visit their personal websites.
Reach out to local performing arts groups to find audience members who want to support other musicians. Send an email out to the music and theater departments at local universities, community theater groups, choirs, bands, and mixed ensembles. Include a basic schedule and links back to your website for more information.
Make announcements at area performing arts events to reach people who already have an interest in music. Ask the emcee to plug the concert series or include a small insert in the program. This is particularly effective if one of the performers is involved in the concert because it gives the audience a chance to see more in an unexpected setting.