Sight reading means that after seeing it written a musician can play the music on his or her instrument with some degree of accuracy. It does not mean that one plays it perfectly, but at least adequately. Some display this ability by humming or singing the written music without the aid of an instrument. Others, by being able to play the music without having to first analyze it, break it down, or practice individual passages. It’s more about recognizing intervals, chords and chord shapes, and groups of notes (phrases) than individual notes. Sight reading is taught (or learned by) most musicians and is often used to measure a musician’s level of musicianship.
Sight reading (sometimes called sight singing or sight playing) is very advantageous for the musician. Having the ability to hear the notes before they are played makes for more accurate playing and learning new pieces in shorter amounts of time.
One of the best ways to speed up the process of sight reading is studying music theory. Knowing the structure and mathematics of music brings about a better understanding of how it is written (displayed on the page). Studying the relationships between notes and chords brings about visual cues that can be used to sight read. And having a good understanding of time and key signatures helps a great deal when seeing a piece of music (and sight reading it) for the very first time. Time and key signatures tell you, in advance, what to expect. For example, knowing a piece of music is in the key of D (two sharps) tells you that whenever the notes F and C appear, they are played as sharps. And knowing a piece is in 3/4 time gives the musician a great understanding of the time values of notes and rests.
Looking for patterns in music is another great way to learn to sight read more quickly. Being able to recognize passages that are repeated allows the musician to look forward and concentrate on other parts of the piece (e.g., knowing that a certain melody line appears many times in a piece of music allows the musician to concern themselves with the music before and after the repeated passage). Written music also has a degree of symmetry and understanding this can help with an overall sense of music structure.
Having recordings of a variety of different kinds of written music is another great way to quickly develop sight reading skills. Carefully and accurately following the recording (with its sheet music) goes a long way in being able to recognize melodies, chords, bass lines and the basic “road maps” of written music.
Most of those who teach sight reading agree that it’s very important to not stop to correct mistakes. They say to never go back to a previous section—complete the sight reading in one “pass”). In other words, think of yourself as sight reading a piece with other musicians as in a performance, and you have to “keep up” with them. Though this might be frustrating for the present, it will speed up the overall process.
Finally, we all learn by doing, so the more your practice the skill, the sooner you’ll be able to master it.