Short timeboxes work because they break apart intimidating, open-ended tasks into easily manageable chunks; no matter how painful creative work is, anyone can do it for 20 minutes. It’s important that you really work during those 20 minutes—intensely and without interruption. But it’s equally important that you stop at the end. No matter how productive you are or how close you feel to entering a real flow state, stick to the timebox. This may seem counterintuitive; after all, if you’ve finally managed to trick yourself into enjoying the process, doesn’t it make sense to run with that as far as your attention span will allow? But the reason this is dangerous (at least at first) is because it runs the risk of setting you up for a long work session that eventually becomes frustrating or disappointing. When this happens, your memory of the session will be that it was both bad and long-lasting, which may further reinforce your procrastination tendencies. On the other hand, if you stop even while it’s fun, you’re more likely to be energized and ready to move forward again once the break is over.