Perfect record keeping is keeping records, not keeping records perfectly.
See this picture? This is what my own record keeping actually looked like, when I was in the middle of a school year.
Perfect record keeping does not mean you have perfectly kept records. You don't have to be perfect. You don't have to grade everything, or even continue the same curriculum for a full year. You don't need a beautiful notebook, either, if simple lined paper or left over graph paper will suffice. You don't have to always use the same colored pen or pencil. You don't even have to grade every class to keep some test grades in only the subjects that have tests.
Can we dissect this a bit further? Let me help you notice a few things about my sample above.
One of the two of my free classes, College Applications Simply Explained, had to be rescheduled last week because I was sick. So, if you missed the one I did