DISCLAIMER #1: This post is primarily aimed at vocalists, however, other members of the band NEED to understand some of this information in order to better work with their singers.
DISCLAIMER #2: When it comes to vocal technique, there's a lot of bad habits, voodoo, and downright false information floating around the music community, perpetuated by well-intentioned bandmembers or family members, people who claim to be vocal coaches (but have no real training), and anecdotal experience.
To try and stop that cycle of misinformation as best I can, I have included links to external resources for most of my points. Where applicable, the links are pulled from academic research, physicians, or reputable vocal coaches. A full list of sources is available at the bottom of the page.
The human voice is the most fragile instrument in a typical rock/pop/country/rap/etc. band, yet it probably receives the most abuse. A vocalist uses their "instrument" (their voice) while rehearsing and performing, and then goes on to use it every waking hour of their life as well. That's a lot of pressure to put on something that needs to hit specific pitches and volumes perfectly.
Imagine carrying an acoustic guitar with you every moment you're awake. You strum it all day. You play it inside where it's nice and warm, you take it outside where it's freezing cold. You just keep strumming... hard, soft, and everything in between. You accidentally spill some coffee on it. At your nephew's birthday party, a little kid grabs the strings with both hands and yanks them with all his might.
After all that, you take this poor guitar to rehearsal and thrash on it for 2 hours, competing for volume with drums, electric guitars, and all the other instruments in your band. How good is it going to sound after all of that stress? After a week, a month, a year of the same treatment? Keep in mind that in this case, you can't change the strings. It's an imperfect metaphor, but it helps us to stop and think about how much stress our voices go through on a daily basis.
If you injure your voice, you could be headed for surgery, or retirement
Why do we need to take our vocal health seriously? Well, if our voices get injured, we are in SERIOUS trouble. If you snap a guitar string or punch through a drum head, you simply swap them out with new ones. If you injure your voice, you could be headed for a traumatic and expensive surgery, or permanent vocal retirement.
Yet, so many vocalists polish off a cigarette, down a shot of whiskey, run up on stage and belt 2 sets over a full band through bad monitors without any preparation or thought about the damage they might be doing. Many of you guys repeat this cycle several days a week.
Mind you, vocal injuries are not limited to amateurs. Many famous musicians, including Adam Duritz, Julie Andrews, John Mayer, and Adele have all had to cancel shows, or entire tours because of vocal injury. It's one thing to miss out on "original band night" at your local bar. It's quite another to miss out on a year's revenue because you didn't take care of your voice. [Reference]
REST & RECOVERY
If there is only one concept you take away from this post, please let it be VOCAL REST. That is the best cure for vocal strain, and the best prevention for future injury. Every time you sing too hard, or too long, or fall into bad technique, you need to allow a good amount of time to recover. [Reference]
"Vocal Rest" means "shut the hell up"
When I say rest, I mean SHUT THE HELL UP. Whispering does not help. Some experts believe it may even be worse than regular speech. You need to be completely silent for the most part, aside from your regular vocal exercises which will help you avoid falling out of shape. You'll have to figure out how much rest you need in order to recover, but DO figure it out, and make sure you stick to it. [Reference]
CHANGE BAD HABITS
You may have to change some pre- and post-show rituals with your bandmates, coworkers, and loved ones. In an interview with Howard Stern, Adam Duritz of the Counting Crows said that he spends most of his time on the road alone, because his voice can't handle the loud bars and parties that go along with touring. That's a lot of fun he's missing out on, but he also knows how important his voice is to the band, and the people who are paying for the tickets. Pro's have to make sacrifices. [Reference]
If you are a normally social person, you might consider some tools to help you commit to your rest. I've seen some tshirts and hats online that say, "I'm on vocal rest." A music student I knew in college carried around a little markerboard on rest days, and used that to communicate with people. Yes, it's awkward, but your health and ability to perform is important.
In addition to shutting up, you need to get your sleep. I'm sure you've heard about the recommended 8-9 hours per night. It varies from one person to another. Either way, get your full night's rest as often as possible, but especially before and after singing. Staying up late and waking up early will inhibit vocal recovery. [Reference]
WARM-UPS
I hate warm-ups. They're awkward, they're repetitive, they're gibberish, and they annoy people around you. That said, if I'm doing anything beyond singing in the shower on a given day, I'm going to the piano and forcing myself to do them.
Sure, you CAN sing without them, just like you CAN play the solo from "Free Bird" without picking up a guitar for a month, but chances are, it won't go as well as it could have had you prepared. It's amazing what a difference warm-ups make when it comes to stamina and range. Work them into your pre-show routine and don't make excuses. [Reference]
HYDRATION
Drink water regularly, and avoid having a dry throat. It helps in the prevention of mucous build-up, and delivers nutrients to your body to keep you and your voice healthy. I'm not going to get into specifics about measuring out the amount of water, because some of that research seems questionable, but as for me, I drink water ALL DAY LONG. When my glass is empty, I fill it. When it comes to performing, I always have water with me on stage. [Reference]
TEAS AND/OR HONEY
They may temporarily ease some of the pain, but they will not magically restore your vocal strength, or eliminate the strain you've placed on your throat. Think of tea as a band-aid, not a medicine. It seems like everyone, non-musicians especially, believe that tea and/or honey will work like Popeye's spinach to bring your voice back to full health. I wish that were true, but sadly, it ain't. [Reference]
Magic throat sprays don't work, and depending on what's in them, may even hurt
MAGIC THROAT SPRAYS
Those magic sprays they sell at music stores are utter horse-pucky. Don't waste your money. They're no more effective than water, and depending on the ingredients, they may even hurt you, especially if they have numbing agents in them. Numbing your voice is bad when it comes to singing. Imagine if you numbed your arm muscles and then tried to pick up a 500 pound weight. Sure, you might do a little better than if you had not numbed, but the post-lifting experience will be much more painful, not to mention dangerous. [Reference]
CHRONIC ABUSE
Chronic strain may mean that your technique is flawed. If you feel pain every time you sing, you should go to an Ear, Nose, and Throat doctor to get evaluated, and a vocal coach to correct any bad habits you've picked up. DO NOT PROCRASTINATE, go now. If you wait, you'll increase the risk of injury, and you'll just keep reinforcing your bad techniques.
Pain is the body's way of telling you that something is wrong. If you're singing, and it hurts, you need to stop singing. If I start to develop pain at rehearsal, I will usually tell the band that we have to go through the rest of the songs without my vocals, or I will at least have to avoid the high notes.
Another option would be to only sing at the beginning of a verse/chorus/bridge to confirm where we're at in the song. (Singing aside, going over a song without vocals is a great way to make sure the band has a song nailed down.) [Reference]
SMOKING (yes, that includes weed)
This is probably obvious. Smoke can damage your vocal folds, it can reduce your lung capacity, and it dries out your throat. Every paper I've read on vocal health recommends cutting out smoking, and avoiding smoke-filled environments. [Reference]
CAFFEINE
Caffeine dries out your throat. Most of the resources and coaches I've encountered over the years recommend cutting it out of your life altogether. It's going to take commitment and sacrifice on your part, but are you a Pro, or aren't you? [Reference]
Alcohol and caffeine are not good for singers
ALCOHOL
I know you're not going to want to hear this, but alcohol is not good for singers. According to this article from the U.S.'s National Institutes of Health, alcohol "can cause the body to lose water and make the vocal folds and larynx dry. Alcohol also irritates the mucous membranes that line the throat." Alcohol can also influence your perception of how and what you're singing, meaning you're more likely to be off-pitch. [Reference 1] [Reference 2]
If you can't hear yourself singing, you're in trouble. If you're competing for volume with drums, distorted guitars, or keyboards, you're going to strain and hurt your voice. Take the time to get the monitor mix right. If you don't know what you're doing, ask someone who knows their stuff to lend a hand. Many sound guys love the chance to fix mixes or to show others the basics.
It's also important to take breaks during rehearsals and shows to give your ears a chance to recover from the deafening noise of a band, and give your voice a chance to rest. During those breaks, shut the hell up. [Reference]
Any reputable vocal coach will tell you that tension and stress are bad for your voice. The problem is, it's not exactly "relaxing" to stand up in front of a crowd and sing. This is to say nothing of any emotional issues that may have come from a fight with your bandmember before the show, or that angry drunk guy in the audience that is heckling the band.
I would suggest finding some sort of regular practice like yoga, structured relaxation, or intentional breathing to help you get control over your breathing (which is how one sings after all), and help manage nervousness. [Reference]
DO NOT CLEAR YOUR THROAT
DO NOT CLEAR YOUR THROAT, especially when you are hoarse. It feels rewarding in the moment, but you are only further straining your vocal cords. I know it sounds tricky, but it can be done. I have not cleared my throat since about 2003, and getting rid of this practice has made a huge difference in my voice. Try anticipating the urge and swallowing instead. It takes conscious and consistent effort to kill this habit, but if you're serious about your voice, you need to do it. [Reference]
When it comes to singing, the road of bad habits is easy to find, and even easier to stay on once you've found it. Your bandmembers and your significant other will rag on you when they hear you doing your vocal exercises... they'll tell you to just down a couple shots of any given alcohol before you go on stage, or to soldier through the pain in your throat at practice. The soundguy will tell you that the monitors don't go any louder, or that you don't need to use a mic that's better suited for your voice. The drummer will say he can't play any softer.
The much harder path to walk is to treat your throat and your body like the most expensive and fragile instrument you will ever own, and to take proper care of it... to change what you eat and drink, how and when you talk, maybe even how you breathe, and how you perform.
One road leads to more fun, a potentially short career, and a lot of costly consequences. The other heads toward better stamina and pitch, and a lower risk of injury, but requires a huge commitment and is usually very tedious. It's not always easy to choose which one to take.
If you can find it in your heart to share, link, or quote anything from this article that you found useful, I'd be very grateful. Also be sure to reach out to me via the comment system or email. All the best.
Don't take my word for it. Here's some further reading on the subject of vocal technique, care, training, and pathology: