Practicing etudes, arpeggios, and scales separates a beginner form a professional flutist. The reason is because the fingers become quicker, more limber, and the brain registers notes much faster, sending the message to the fingers to move. Practicing etudes, scales, and arpeggios makes playing fast passages much easier and will also help when sight-reading new music.
Practicing Correctly
Every flutist must practice sheet music for their orchestra, concert band, or other ensemble. However, they should focus on the basics and drills like any other musician and even sports players. A football player doesn't just practice playing a game every day, they run drills, learn how to block, sprint, and learn to tackle.
All of these skills combined will help during practice, and during a suspense filled game. Undeniably, it is the same for a flutist, and any musician. They need to practice tone, tuning, articulation, rhythms etc. All of this will help when they are in the practice room, and in the concert.
Practicing Scales
Scales should be approached slowly at first. Start with the chromatic scale with the eventual goal of playing it like Nikolai Rimsky-Korsakov's Flight of the Bumble Bee. This will take months to years to perfect, and will be a great way to practice in the long run. Move on to major and minor scales between chromatic scale practice. Even if all the notes are known, flutists should listen to the sound and tone of every note and not move until each note resonates perfectly. Increase the speed as tone improves. Aim to play the scales as fast as possible with no mistakes.
Once the scales are memorized, which shouldn't take too long at all, add rhythm and articulation studies by using a scales book. Any standard practice book will have scales in the back of the book. Pares Scales for Flute or piccolo by Gabriel Pares is a good book with wonderful scale exercises that also help teach articulation, rhythm, tone, and tempo.
Practicing Etudes and Arpeggios
Etudes and Arpeggios help musicians recognize groups of notes in a family and how to jump octaves effortlessly. The notes move up and down like waves and those groups of notes will improve brain response time and finger agility. They are also much more beautiful and fun to play than scales. The same approach should be taken as in scales. Start out slow and long and go faster as each speed is perfected.
Improving Finger Response to Visual Music
Practicing scales, etudes, and arpeggios with every major and minor scale will train the fingers and the mind to recognize the notes quickly. Sometimes, music will call for an B sharp instead of an A flat, which is the norm for music, and the musician has to be quick on their toes to recognize this note.
Perfecting the flute is a never ending goal. A flutists can always get better, a runner can always get faster, and a football player can always hit harder. It takes grueling hours of practice that all pay off during the ultimate game, the ultimate concert.