Being Tired Is No Excuse
Hyrum W. Smith made the startling accurate quote that: "Character is the ability to carry out a worthy decision after the emotion of making that decision has passed."
Being tired is never an excuse for doing less than your best. Plan to be weak and you will make yourself stronger. Every decision you make goes into the results of what you achieve. Instead of staying up late to watch that last television show, meditate over the day's events while lying in bed. Rather than focusing on the goal of "just making it through the day," focus on "making this day count toward the goals of tomorrow."
All this might sound "cheesy" or "over-the-top," but I found that those who think so rarely find the success they find so much time to talk about.