Usually it is because of poor breath control and lack of activation of one's diaphragm. Therefore:

THE ONLY SAFE way to learn the correct singing techniques & to improve properly IS to take OFFLINE face-to-face singing lessons with a fully trained vocal teacher (in case you do not have a teacher yet)! The teacher HAS TO BE in the same room with you, so that he/she could give you proper feedback.

Please do NOT rely on any dodgy web tutorials because that way you can misunderstand things VERY EASILY and develop bad habits, hoarseness, vocal nodules and other nasties IN NO TIME, and even though you would sound good! It is always much wiser to invest a little bit of your money/time to face-to-face lessons rather than wasting the same amount of money (or even more!) to frequent ear-nose-throat specialist visits due to aforementioned problems, so please reconsider this. If you can't afford vocal lessons, then joining a choir is the only SAFE alternative option. And believe me, but even MANY of those who have music as their hobby DO take lessons as well!

Always remember to warm up your voice properly, but please know your limits and don't overdo your voice! Remember the diaphragmatic support, do not strain your throat too much! Also, remember good body posture!

Avoid fizzy drinks (burp danger), dairy products (mucus risk), caffeinated products (coffee & tea included, they dry up your throat) and spicy food (irritation risk)! You can consume these things, but NEVER before singing!

Do NOT shout, yell, scream nor otherwise abuse your voice AT ANY TIME! Also, please respect your vocal range; if your teacher says you are, say, more of an alto (baritone if you are male), then you ARE more of an alto (baritone).

DO NOT try to imitate anyone famous, that will usually give you just bad habits and even damage your throat. You are YOU and your voice is unique, so please learn to cherish that. The world does NOT need copycats.

Do NOT sing, whisper, shout, yell nor scream if having a sore throat/cold/flu, Also, do speak as little as you can if you have flu/cold/sore throat!

Remember to drink at least 2 litres of room-temperature still water every day, not just during singing days!

Smoking is a big no-no, as is inhaling secondhand smoke. Also, avoid staying in dusty and/or moldy environment.

Many singers wonder how to sing high notes with power and richness. The notes that fall within speaking voice range are easy to sing, but higher notes are notoriously difficult for beginners.

If you’d like to learn how to sing high notes without compromising your vocal quality, use these tips to get started:

How to Sing High Notes: Finding Your Upper Limit

You can find the upper limit of your vocal range by singing progressively higher notes until you can no longer sing comfortably. The highest note you can sing without straining is the top note on your natural vocal range.

Use a guitar, organ, or other properly tuned instrument to help you identify the notes in your range. Play a note, then match your voice to it. Keep doing this until you reach the top of your range.

Any notes above the top of your vocal range will require some practice. The goal is to learn how to sing high notes with good vocal control and without straining your voice.

How to Sing High Notes: Spanning Your Vocal Break

As you reach the top of your range, you will notice that there is a point where your voice changes in quality. The deeper notes are sung in your “chest voice”, which is close to your regular speaking voice. This is the voice that resonates deep in your throat or chest.

At some point, your voice will shift to a lighter, airier sound that reverberates in the top of your throat or back of your mouth. Some people describe this voice as nasal, but that’s not accurate. This higher, thinner voice is known as the “head voice”, because it resonates higher in your head.

The point where this switch occurs is known as your vocal break. Beginning singers find it difficult to sing notes immediately above and below this break, but with some practice, you can learn to bridge this break and sing most songs seamlessly.

How to Sing High Notes: Improving Your Head Voice

There are two major steps you can take to improve the quality of your head voice. First, you’ll need to develop your “mixed voice”, which is a combination of your chest and head voices.

The mixed voice is the result of practice; most people don’t come by it naturally, but experienced singers incorporate it so smoothly that it’s impossible to tell when they switch from chest voice to head voice.

To strengthen your mixed voice, you need to sing the notes around your vocal break. As you sing progressively higher, you should practice using a bit less of your chest voice and a bit more of your head voice. You can practice this skill by paying attention to where each note resonates in your throat and mouth, and putting slightly more emphasis on the “head” notes as you go along.

Over time, you will learn to place the notes where you want, making the transition from chest to head voice very smooth.

How to Sing High Notes: Breath and Diaphragm Support

The second part of singing higher notes with ease is learning to use your breathing and diaphragm to support the high notes. Without breath and diaphragm support, your head voice will sound thin and reedy. With breath and diaphragm support, it will sound rich and strong like your chest voice.

Practice rationing your voice as you exhale a note, not letting it out too fast. This will help you sustain high notes and give them just the right amount of breath support.

Your diaphragm is the muscle in your stomach area that flexes when you laugh or exhale sharply. Practice flexing it as you sing to give extra support to your high notes for a more powerful sound.

With your full vocal range and the power of your breath and diaphragm behind you, you’ll soon learn how to sing high notes like a pro – and how to belt out money notes your audience will never forget!

The ONLY SAFE way to improve properly is to take face-to-face singing lessons with a fully trained vocal teacher! Please do NOT rely on any dodgy web tutorials because that way you can misunderstand things VERY EASILY and develop bad habits, hoarseness, vocal nodules and other nasties IN NO TIME, and even though you would sound good! It is always much wiser to invest a little bit of your money/time to face-to-face lessons rather than wasting the same amount of money (or even more!) to frequent ear-nose-throat specialist visits due to aforementioned problems. If you can't afford vocal lessons, then joining a choir is the only SAFE alternative option.

Always remember to warm up your voice properly, but please know your limits and don't overdo your voice! Remember the diaphragmatic support, do not strain your throat too much! Also, remember good body posture!

Avoid fizzy drinks (burp danger), dairy products (mucus risk), caffeinated products (coffee & tea included, they dry up your throat) and spicy food (irritation risk)! You can consume these things, but NEVER before singing!

Do NOT shout, yell, scream nor otherwise abuse your voice AT ANY TIME! Also, please respect your vocal range; if your teacher says you are, say, an alto, then you ARE an alto. DO NOT try to imitate anyone famous, that will usually give you just bad habits and even damage your throat. You are YOU and your voice is unique, so please learn to cherish that.

Do NOT sing, whisper, shout, yell nor scream if having a sore throat/cold/flu, Also, do speak as little as you can if you have flu/cold/sore throat!

Remember to drink at least 2 litres of room-temperature still water every day, not just during singing days!

Avoid inhaling secondhand smoke!