Everything "the Student" gave you already is good advice.

Also, consider your current stance, or the way you move. You must start on balance and finish every step back in perfect balance with a stable stance.

Moving slow as the Student suggestion will make bad movement more evident because speed can hide the rough spots.

Are you keeping you weight more on the back foot as you generally should?

Are you always moving the trailing foot the exact same distance as the first foot to move so that you will be back "in stance"?

Are you taking long steps? Most of the time this is a poor idea.

When you through, are you staying within your natural range or (incorrectly) reaching out too far?

You coach should have you concentrating on stance, movement, and balance until you have that automated. Punching mechanics must then be added so that you don't disturbing that stable platform.

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HerbM