Be aware that when you travel, background noise in cars, airplanes, trains, and other vehicles forces you to speak louder than normal and can be detrimental to your voice. Before traveling, prepare your body by super-hydrating, drinking eight to 10 glasses of water a day for several days beforehand. Avoid alcohol and caffeine while performing. As mentioned above, they can dry your body and vocal mechanism. Alcohol can also alter your perception of how loud you are singing, impair your ability to sing in tune, and lead to unnecessary strain.
Drinks containing alcohol and caffeine can also lead to reflux laryngitis.
Throat clearing is hard to avoid when you have a stubborn spot of thick mucous rattling around and you're trying to sing. Clearing your throat will remove the bothersome mucous but can also irritate the leading edges of the vocal cords. When practicing, try to sing the mucous off. If you must clear your throat, do it gently and avoid habitual throat clearing. Warming up before rehearsals will help you avoid straining your voice.