Knowing that I have good systems in place, that are designed to automate all the mundane tasks. That way I can concentrate on the more important stuff.
And yes I use Post-It notes to stay on top of things. You'd be amazed what happens, if you take a Post-It note, Evernote, Zapier, IFTTT and SalesForce:
Would you believe a Post-It note automates my Productivity?
