This is a harder question to answer than you may think. In an ideal (musician’s) world, the only thing that should matter is if a band is capable musically and sounds good. I have been in bands with amazing musicians playing what we thought were smart tunes that went absolutely nowhere because we lacked the things that would set us up for success. Here are a few of those things:
Marketing Materials– Your band needs a good name, a quick pitch to what kind of music you play, and the required logos/photos/video etc. You may not think you need it, but you need a website. Even in the age of ubiquitous social media, a good website will get you hired more than how many facebook fans you have. You need a good video. Good means it shows what you look like, what you sound like, and how much fun your audience has. It doesn’t need to be professionally shot but it needs to be clear and informative.
Concise Song List– A band’s song list tells me more about a band than any bio or promo shot could. It shows your tastes, your musicianship, and your creativity. It doesn’t have to be avant-garde but there should be songs that stand out from the crowd of competing bands. Clients will usually pick their band on video and song selection alone so make sure they are accurate and up-to-date.
Musical Aptitude– You need to be able to play the material handily. Make sure you are rehearsed and prepared. In all reality your singer is the most scrutinized position in the band. If your singer sucks, your band sucks. Make sure your lineup is as solid as it can be.
Showmanship– You need to be able to bring people in, keep them drinking, and keep them entertained. You need to have solid stage presence. You need to be interactive with the audience. You need to be funny and engaging in between songs (even if it’s rehearsed). You need to be rockstar, emcee, and party host all in one.
Reputation– Your performance starts the second you enter the venue and ends when your pull out of the parking lot after load out. You need to be polite, professional and cordial to everyone you deal with. That applies to parking attendants, doormen, sound engineers, bartenders, event planners, and client contacts. Be accommodating. Be flexible when possible. Get to “yes” as quickly as possible when plans are changed. Your ability to work with others will keep you in business much more than your ability to put on a good show.
These are the biggest things you have to possess if you want to build a band, run a business, and get solid work. Even then they are no guarantee for success. This is a cutthroat industry and your ability to adapt and improve will determine where you go.