Monday Hour One Calendar Color+ Friday Hour Done

I just finished the Monday Hour One course. I can’t wait to try it on Monday! Two questions: First, I noticed in the calendaring video that only one color was used regardless of the activity. Is that intentional? Does using different colors help or hinder? In my current calendaring, I use one color for money-making activities, one for personal activities, one for one-off activities. What’s your take on that? Second, I heard a reference to “Friday Hour Done, but am having trouble locating the description of that. Can you share what is meant by that, and when and what we are supposed to use that hour? Thank you!