I think it is important to first start with an awareness of the time you have available to commit to promotion. Having something in mind up front will keep this from being overwhelming. Also, know your past marking experience will serve you well. A quick parallel though is this follows rules that are a bit more informal and social, think trading business cards and connecting with buyers on steroids. In this world consistency and value are king.

It’s important to keep a few things in mind before diving in:

• Make sure you are adding accounts only if you have time for them. To be honest, for the art world, I think Facebook is better, but you have to be diligent about using/setting-up lists to keep public/private worlds separate. It might be worth checking out Twitter and Tumblr. For all of them, there are public search options (search.twitter.com), in the advanced search you can search by location too. Use these to gauge conversations on art or your medium or other criteria.
• Consider your overall brand, as in, what are you trying to communicate.

Thinking a bit through the above will help a lot. These articles on using social media in 10 minutes a day gives you a reference on the daily activities you should have. If more time is to be had, then just expand proportionally. The first three are great starters, the second + webinar will go a bit more in-depth into leads and a more traditional “sales funnel.”

• 10 Minute Per Day Social Media Plan
• How to Manage Your Social Media Marketing in 10 Minutes Daily
• How to Monitor Your Social Media Presence in 10 Minutes a Day: Presentation Slides | Webinar Recording | Article

If I were to summarize you (1) talk a little about yourself and your events, (2) share valuable things, and (3) socialize with your network. The biggest lesson is that in real life we don’t like the colleague who only talks about themselves, so don’t let that dominate your conversation. By building trust in other valuable ways, your network will grow to view your self-promotion as on-message and equally valuable.

For your upcoming events, I’d make sure of the following:

• Confirm/Create landing page for event, such as a Facebook, Eventbrite, or other such page.
• Connect with individuals who are relevant in some way to seeking interest in your work or upcoming shows.
• Share media (photos/videos) to connect individuals to your work.
• Start socializing with the primary goal as acting as a valuable resource.
  Cross-market with any performance collaborators.

If you focus on building a positive network for yourself up front, you’ll be able to message more strongly and to a more receptive audience closer to the performances. Note, time is money, and it may be all you have time for is to send updates about what you are doing. This is better than nothing, but to really reap the benefits you hear touted about social media, you must engage socially with the community you are trying to build.

Hope this helps!