Find out what key the music is in. Look at the first and last note or the root of the chord for the piece, which will often tell you the key. Consult the circle of fifths tool in order to discover the key and its relative minor, which will also help to determine the tonic note, or starting position, for the piece. The circle of fifths allows you to count the number of sharps or flats in order to determine which key the music is in.
Write out the diatonic scale starting with the tonic, first degree, and ending at the leading tone, seventh degree. Using three lines, write out the names of each degree, the music notes for each degree, which is determined by the key and the numbered scale degrees for the scale.
Analyze a portion of the music, turning the individual pitches or chords into scale degrees. Remember that chords can be inverted, which means that the root note for the chord is not always the note closest to the bottom. Write out each pitch in a chord and look for triadic relationships in order to find the correct root note.
Look for patterns in the music, such as the well-known Western musical cliche of 1,4,5,1 or some other form of leading back towards the tonic, which is 1. Other examples may include 1,5,4,5,1 or 1,5,7,1. In Western music, it is usually either the dominant or leading tone that best leads back to the tonic.
Look for interval relationships between segments or phrases of the music. Find the interval by using the diatonic scale, written out in Step 2, to count the number of scale degrees between each event in the music. Remember to look for transitions in the music to different keys, as indicated by accidentals included in specific phrases.