At first blush, it doesn’t seem like anyone would ever need any concert tips. You think to yourself, “I’ll just buy the tickets, show up at the venue more or less on time, and coast through the night on a wave of sing-along choruses.” But making the most of a concert night isn’t always as easy as it seems. When’s the right time to buy merch? What if there’s a tall person blocking your view? And how on earth can you remain civil to your fellow man in the chaos of the mosh pit?

There are a lot of unspoken concert rules, and even if it’s not your first time going to a concert, you might not know them. This is why we turned to staff members of four nightlife venues that have seen it all: Chicago’s Double Door and Empty Bottle; Seattle’s Neumos Crystal Ball Reading Room; and Los Angeles’s Whisky A Go Go. Together, they helped us put together the definitive guide of concert tips that will have you enjoying a show or music festival without becoming the butt of the band’s jokes.

Use Your Smartphone Sparingly

Among music fans, few things inspire more vitriol than smartphones at concerts. Plenty of bands have gone on record saying they hate it, but the venues tend to have more nuanced feelings.

“I have mixed emotions,” confesses Guy Keltner, the marketing manager of Neumos. “As a fan, I hate it. Nothing pisses me off more than someone filming the whole song and covering my view when I’m trying to watch the show.” But Keltner also admits that it makes his job easier as a promoter. “I love getting tagged in Twitter and seeing photos from a show. When people see pictures from a sold-out show and get that fear of missing out, it really helps me [do my job].”

Luke Iblings, the talent buyer at Whisky A Go Go, is similarly ambivalent. “From a promoter’s standpoint, I think it’s great seeing all the pics and vids running rampant on the net. From a concert-goer’s standpoint, it’s pretty annoying.”

The bottom line? You might be helping out the promoters, but you’re definitely annoying somebody behind you. And anyway, according to the Empty Bottle’s promotions/street-team coordinator, Mike Gebel, “taking video on your phone is stupid and it almost always sounds like s---.”

Buy Merch Before the Show Starts

If something on the merch table catches your eye when you walk in, don’t think twice—just buy it. “If you know you like the band or it’s an opener you want to support, go do it as quickly as possible,” Keltner advises.

Nate Arling, who works as booking manager at Double Door, agrees with this particular concert tip. “I’d say buy it right away,” he says. “Sometimes you’ll forget, or they’ll be sold out of that shirt by the time you get to it.” Sure, holding a poster for three hours doesn’t sound so appealing, but some venues (the Double Door, for example) will offer a coat check for merch.

Arrive As Close to Door Time As Possible

It can be tempting to skip an unfamiliar opening act, but know that by doing that, you’re not only risking missing out, you’re likely forsaking a spot up front. To secure a great spot, Arling has a simple recommendation: “Just get here as close to door time as possible—maybe about a half hour before doors.”

Of course, even that doesn’t guarantee anything. “I’m one of those guys who just shoves his way to the front no matter when I arrive,” Keltner admits. “No matter what, people are going to shove in front.”

Tall People: Be Aware Of Your Surroundings

Speaking of shoving in front, why does it always seem like the tallest guy in the room is standing directly in front of you? Gebel says that it’s not exactly rude for a tall person to sneak up front, but “it can suck for shorter people. Fans—tall or not—should always try to be aware of their surroundings.”

That’s a good concert rule to follow in general, according to Arling. “I think anyone trying to help others have a better concert experience is always a good thing.”

Crowd Surfing: No. Moshing: Sure!

Is crowd surfing cool? Arguably. Is it safe? Definitely not. Though crowd surfing isn’t always banned outright, all four of our experts had bad things to say about this common concert activity. “So many people fall backwards on their head or neck,” Arling explains, “so we try to be pretty strict about it.”

Mosh pits, on the other hand, are pretty much fair game. “If you are going to book certain types of shows,” Iblings explains, “you must accept the fact that there will be mosh pits. I am personally all for them!”

Gebel mostly agrees, but he says it’s best when fans police themselves. “There’s definitely a safe way to do it, and the collective fanbase is better [off] if everyone’s looking out for the health and safety of one another.”

The Most Important Concert Tip of All: Don’t Be a Jerk

Tip your bartenders. Don’t talk loudly (“or whisper loudly into each other’s ears,” adds Gebel) during quiet sets. And whatever you do, don’t throw a punch at the bouncer.

At the end of the day, “I just wish people would be a little more polite,” says an exasperated Keltner, who has witnessed his share of horrors over the years.

Ditto for Iblings, who has been booking shows on the Sunset Strip for 15 years. “I’ve probably attended 10,000 concerts in my lifetime, [and] I wouldn’t even know where to begin with all the crazy things I’ve seen.”

So do these guys a solid and be respectful of the staff and the performers. In other words, don’t be a jerk.