“Yesterday is a cancelled check; tomorrow is a promissory note; today is the only cash you have - so spend it wisely.”
“Yesterday is a canceled check: Forget it. Tomorrow is a promissory note: Don't count on it. Today is ready cash: Use it!”
“Today is today, only today... tomorrow...it will only be yesterday.”
“Today is all you have, so gather the best from it for tomorrow too quickly becomes yesterday.”
“Today is what you have and the only thing you can work with. Yesterday is gone and tomorrow isn't here yet.”
“If you realize you aren't so wise today as you thought you were yesterday, you're wiser today.”