@MARKK2556 Memorizing the formulas is very very helpful and will prove worthwhile through all three levels. Of course, being fast on the calculator is also very helpful.
We just developed a 9 page formula sheet for Level I. Let me know if you’d like to be a free beta tester of a PDF version of it. So far our feedback is that its the best one available, being the most comprehensive and yet not overwhelmingly long.
We have a free 15 minute calculator guide as well: https://www.youtube.com/watch?v=Ehchb6Zvag0
Hope that helps!