Social media is a huge tool in self promotion for artists and musicians today. That being said, many artists don't use all the tools available to promote their music, and often fall short in their social media strategy.
In this article posted by Reverbnation you will find some great information and tools that will help improve your social media strategy today!
http://blog.reverbnation.com/2014/09/17/effective-social-media-strategies-for-musicians-becoming-a-digital-storyteller