Don't expect motivation to stay consistently high throughout every practice. Decide before you begin that your commitment will stay strong even when your motivation changes.
During:
When motivation fades, don't let it slow you down. Focus on doing the next repetition, drill, or effort the best you can. Let your commitment—not your motivation—drive your performance.
After:
Did today's MindRep help you? How did today's MindRep help you? Do you want to own it and make it a consistent part of your training?