Humans are creatures of habit. To start with, it's important to endure the
greatest challenges. Ideally, aside from eating, sleeping, and bathing, you
should dedicate all other time to studying or working. For example, studying
for 16 hours a day. This way, nothing more difficult will overwhelm you later
because your body has already experienced the toughest day. If you then reduce
your study time to 12 hours a day, it will feel relatively easy. However, for
those who are used to studying only three hours a day, 12 hours would seem
impossible. Therefore, the beginning is crucial; you must push yourself to
the limit right from the start.