What: Playing the maqām scale up and down cleanly while hitting the neutral note precisely.
Why: A clean scale is the base of every melody in the maqām; the neutral note is the flavour that distinguishes it.
How: Play slowly, hit each degree, and mind the quarter-tone especially (like sīkāh in Rast) without rounding it to a Western semitone.
Common mistake: Playing the neutral note as a Western semitone, losing the maqām's character.
Exercise: Play the Rast scale up and down slowly, focusing on the accuracy of the sīkāh.