Our company was born of a passion for music. Which means in addition to our work for artists and labels as clients, we also follow a lot of them on Facebook simply as fans. And as we see bands' promotional efforts come through our news feeds, we tend to see lots of the same mistakes. Here are a few of the most common:
Lack of Context: If your aim is to reach beyond your existing fans to create new ones, a ticket link is about the worst thing you can use for your campaign. The likelihood of someone seeing an ad from a band they're not familiar with and proceeding to buy a $15 ticket is close to zero. To reach new ears you need to communicate WHY they might be interested, then provide an easy path to become a fan. Once they're a fan, THEN you can sell them a ticket.
Not Segmenting Your Targets: Your existing fans are going to be your biggest source of ticket sales by a vast margin. So it's important to guarantee you reach 100% of them, preferably a few times. When it comes to other targets, you are aiming for wide coverage, but you don't necessarily care who among them sees it. Too many bands do "Campaign A: Targeting our fans plus fans of Band X and Band Y". You'll get much better results by separating into "Campaign A: Targeting our fans" plus "Campaign B: Targeting fans of Band X and Band Y".
Poorly Formatted Images: Take the time to learn the sizes that Facebook prefers for each type of post and ad. It looks totally amateur to have images cropped awkwardly because you used the wrong size. For a link post, this means 1200 x 627px.
Putting It On Blast: With the advanced posting options that Facebook offers, there's no reason you need to show fans content that has nothing to do with them. A fan in New Jersey doesn't care about your show in San Diego. Use geo-targets to limit the audience for posts, or better yet take advantage of "Dark Posts" to push specific content out to each market.
Slow Your Roll: We see bands doing this all the time....the show is in three weeks so they set up a three week campaign. The problem is that by about day four everyone has seen your ad so many times that they are ready to block your page forever. Build in some breathing space. Try having the ad turned on for three days, then off for four days. The idea is to respectfully remind people about your show, not beat them into submission.
For more on this topic check out "Facebook Marketing For Musicians"