For most people, breathing with the upper lungs is adequate; they do not need to maintain the same level of airflow control that a singer requires. Vocalists should use their lower lungs to achieve control. Filling the lower lungs requires the use of your diaphragm rather than your chest. It is easy to distinguish between the two types of breathing. Take a deep breath. You are breathing with the upper lungs if your chest and shoulders are moving. You are breathing with the lower lungs if your body is not visibly moving during the breath.
Practicing is required for a singer to build proper vocal control. It is common for many singers to over exert themselves by practicing too much. There is even a point where too much practice is detrimental. The length of practice a singer can use varies significantly, making it difficult to determine the ideal practice time. Beginning singers should not practice more than 20 to 30 minutes a day. Add more time as you develop more control. Vocal training is identical to any other form of muscle training. Any excessive strain in your vocal muscles should be taken as an indicator to stop practicing for the day. Only well trained, experienced singers are going to be able to benefit from an hour or more of practice a day.
Some substances or types of food can have a variety of detrimental effects to singers. These effects are temporary, so you only need to avoid the foods prior to a performance or practice. Avoid pepper or spicy foods. These types of foods cause throat irritation which affects vocal control. Dairy foods cause excessive amounts of mucus and phlegm to build up. Salty and fatty foods can dry out the throat. Any type of food that causes acid reflux to build up in your body should also be avoided. The types of foods that cause this vary from one singer to the next.
The vocal cords need to be properly hydrated to function properly. Only water can accomplish this. Sugar, caffeine and alcohol are detrimental to your vocal control. Drinking water does not immediately hydrate the vocal cords. The water still has to pass through your digestive system before reaching the vocal cords. Start drinking water at least 20 minutes before a performance or practice. This gives the water enough time to go from your stomach to your vocal cords.