There is the notion among many that you either can or cannot sing. This is not true. Many people can learn if they get some good tips on how to sing. These start with practical ideas anyone can try.
First and easiest of all, think about what you eat and drink before singing. Not everything goes. Eating at all should be regarded the way one would think of food before swimming. Before a performance, give yourself at least half an hour or even longer.
The ideal drink is water. Herbal tea is okay, though the best temperature for fluid is lukewarm. No pop or alcohol: these cause you to burp and sometimes irritate the throat. Avoid anything that you are sensitive to, like sulfites, and foods which cause mucus (such as juice or milk) or coughing (like nuts).
Breathing as a singer is different from the breathing we do all of the time without thinking. Learning to control breath will enable a singer to direct notes, even work on dynamics. Feel your upper abdomen as you draw breath from the diaphragm, not from the nose or throat.
Work by alternative activities. Take a deep breath and sing an exercise like scales or intervals. Push out short breaths on one note, singing just ha, ha, ha.
Stand up straight, or sit straight in your chair, feet flat on the ground. Never slouch or sink into yourself. Keep the chest up, shoulders back and down. Never stretch your head back to force out notes as this simply cuts off air rather than giving you more power.
Be confident. Nerves are one of your worst enemies. Remember that half of the pleasure when watching someone sing, in a choir for example, is seeing members interested in the music. Nerves will cause the voice to wobble; anxiety takes away that precious air you spent so much time learning to control.
Get on top of each note. If you try to reach from beneath, the result will fall flat. Your aim is to drop down, not hover above in a screech or with a sharp effect. Be brave; aim high.
Practice is key, as with any skill. Throat muscles need to develop. They require the exercise of scales, of trying open and closed notes. You might notice it is easier to sing open vowels with clarity and volume than to open up the sound of a consonant. Over time, range will develop. One to one and a half octaves is normal. Extending personal range by half an octave should be considered an achievement and, with this extension, confidence in these notes will grow.
If you want to learn more about learning how to sing take a look at Tips On How To Sing