How to Protect Yourself
By now you should have a clear idea that vocal distress can come from illness, external sources, or misuse of the voice. You'll want to find some ways to defend yourself against these challenges. Your voice isn't an instrument you can return or replace if it's broken or damaged. It's much easier to protect and care for it now. Usually it's easier to think of what positive actions we can take rather than giving up what's been a long-term habit, comfortable, or pleasurable. As you look through this list, think of one or two actions you might adopt, and then keep adding to those as you're able:
Drink at least eight to ten glasses of water daily.
Use a humidifier to keep moisture in the air.
Use saline spray rather than medicated spray for your nose.
Get at least seven to eight hours of sleep.
Keep a food journal to determine any possible patterns of allergy, discomfort, or time intervals necessary between eating and singing.
Drink water and herbal tea at moderate temperature, neither too hot nor too cold.
Get plenty of exercise, especially calming practices such as yoga.
Practice proper vocal technique and build up beneficial muscle memory.
Moisture is one of a singer's best friends. Besides drinking plenty of water, you can also inhale steam. There are inhalers with molded plastic masks to guide the steam. Simply boiling water on the stove also works well, as does turning on a hot shower and filling the bathroom with steam.
The more serious you are about singing well, the more careful you need to be with your general physical health. Certainly no one is perfect in the quest for physical and vocal health, but if you can identify which things are helpful or harmful, you'll at least have that information. Then you can make decisions based on the immediacy of your vocal needs and your willingness to accept the consequences of those choices.