What is the best way to master memorizing the Quran and not forget it, given the difficulty in memorizing due to work circumstances, and knowing that I have completed memorizing eight parts?

The advice for memorizing the Quran, especially with numerous preoccupations, is to frequently review and repeat the newly memorized portion while reducing its quantity, and to repeat what you have memorized until it becomes firmly established, then to link the new memorization with the previous one.