Never put off till tomorrow what you can do the day after tomorrow just as well.

In the article that this quote appeared, Mark Twain expresses a desire to "snub" Benjamin Franklin's popular maxims. Specifically, this quote was meant to be a sort of anti-proverb to Franklin's advice: "Never leave that till tomorrow which you can do today." Extended Quotation:

Never put off till to-morrow what you can do day after to-morrow just as well.