What I learned from trying to compress a day's work into a single window.
The premise is simple: every day, one 90-minute block where I do the most important thing. No email, no notifications, no meetings. The phone goes face down. The browser stays on one tab.
I've been doing this on and off for about three years. The off-periods always look the same — a meeting creeps in, the time slides, and within a week the block has disappeared. Then I notice the project I cared about hasn't moved in a month, and I rebuild the discipline.
The thing nobody tells you about deep work is that the rest of the day gets easier, not harder. After ninety good minutes I genuinely don't mind admin. I don't mind email. I don't mind the meetings. The pressure is off, because the thing that mattered most is already done.
It's the simplest piece of advice and the hardest to keep. I'm writing this between a 9:00 and 10:30 block.