"The mistake is when you put more effort into the promises and less into what you deliver. Promise a lot but deliver even more."
This holds true not only to what you promise others but is even better if we apply it to ourself.
Under promise to yourself but over deliver. How?
That you have to find out for your unique situation.
I am trying to do the same by promising myself to write 2 posts per week and trying to do more. Promising to exercise thrice a week and doing it more.