You can write the 8 note-heads of the scale immediately, since you are told to
write a descending scale of Ab. Leave big spaces before each note so you can add
the accidentals in the next step. Pick a high note on the stave, since you are writing
the scale from top to bottom. Don’t be put off by the “begin with tonic” - just a
fancy way of saying start with the key-note of Ab. We have an alto clef here - the
“kink” marks middle C as the 4th line up, so The second line would therefore be too
low to start the scale, so pick the “A” space above the middle C line. (Writing notes
in the alto clef is like writing them “one note down” compared to the treble clef
- e.g. A’s in alto are written like G’s in treble etc.)
Now add the accidentals. A “flat” major will always have flats in it - it’s on
the left hand side (6 o’clock to 12 o’clock) of the cycle of 5ths clock-face. You
may remember that Ab is at 8 o’clock on the clock face, and so has 4 flats. If you
forget that, work though the sequence of flats in a key signature and go one beyond
the key note of Ab : Bb - Eb- Ab- Db (This always works for “flat major” keys).
So you have to write accidentals flats before every B,E, A and D note.
