It's really up to you, your personal approach to practice - and whatever works. You might just use each wave once during the month, or you might use every recording many times over.
I recommend looking for a way to build a relaxed but regular commitment into your routine. How that looks will be a function of your life and schedule, of what you want and of when/how the windows are. Some people practice first thing every morning, some do evenings. Some have a dance during lunch-break and some keep the weekend clear. As Gabrielle Roth put it, find "the discipline to be a free spirit"...