This may not seem like the most profound advice you will ever receive, but it could save you both embarrassment and setback: be nice to the staff.
Have you ever been at a restaurant and the person you are eating with is rude or condescending to the waitstaff? Not a good look, right? It might be downright uncomfortable or maybe even a deal-breaker on a date. However many musicians act like this at a venue or event without giving it a second thought.
The staff who work around a music event can be varied: bartenders, waitstaff, promoters, photographers, sound techs, etc. Even if these people are not directly involved with you as an artist, you need to be respectful and courteous to them because they can and likely will have an effect on your event. Even if they don’t, a bad reputation can destroy an artist’s opportunities or image.
Some of these ramification may be more obvious than others. If you are a jerk to a sound engineer, you may find your set sounding less than ideal. While you may consider this petty or unprofessional on their part, they may consider your bad attitude petty or unprofessional. That is not to say that every engineer will let personal feelings affect sound but they are humans like the rest of us and deserve to be treated with respect.
What about the booker? So the show didn’t turn out the way you wanted it to. But the booker may single-handedly control whether or not you get another gig at a given location and unless you want to sabotage your opportunities, it’s probably best not to let your temper or negativity enter the conversation. It’s okay to stand up and advocate for yourself, but there is a right and wrong way to communicate your concerns.
What about other people who may have an affect on the production? If you are playing in a bar, it doesn’t matter that you are the act performing that night, you should be just as nice to the bartender and waitstaff as anyone else and if you fail to do so, you might find yourself waiting a long time to be served. Think you can be a jerk to the photographer? Maybe those pictures don’t turn out as well as you thought they would. Talking down to a promoter? Don’t expect a long and healthy working relationship that could benefit your career.
The point here is not to be fake or brown-nose to get what you want. You should treat everyone with respect and kindness if for no other reason than it adds a level of professionalism to your image and it will almost certainly open more opportunities for you. And while it is possible that you can be the most irritating diva around and still get star treatment, you make quite the gamble as an indie artist just to feed your ego.