Making something simple is very difficult.

Don't avoid eye contact and don't be late

I spend 90% of my time with people who don't report to me, which also allows for serendipity, since I'm walking around the office all the time. You don't have to schedule serendipity. It just happens.

I think Twitter is the future of communications and Square will be the payment network.

There's an entire universe in every single tweet, and it all really depends on the content as far as how it's going to spread.

Your job as an executive is to edit, not write. It's OK to write once in a while but if you do it often there's a fundamental problem with the team. Every time you do something ask if you're writing or editing and get in the mode of editing.

As CEO, my main job is editor-in-chief.