When you practice, ask yourself questions. Don't just go through the motions and get reps in without analyzing what you're doing.

Am I playing the right heights?

Am I playing with great technique?

Am I playing with great height separation?

Am I rushing or dragging?

Do all of my diddles sound the same?

The list could go on forever, but it is your job to know what questions relate the best to you. As you practice, write down questions that will keep your playing honest. Use these as mental checkpoints so you never practice without intent.