One of the best productivity methods comes from an age before personal computers and iPhones, when the closest thing to a push notification was the interoffice mail system. Back in 1918, public-relations pioneer Ivy Lee was hired by a major steel company to kick-start its office’s efficiency. Lee's advice to the Bethlehem Steel Company’s executive still holds up today, as James Clear writes in Fast Company, in part because it’s just so simple.

Here are Lee’s five steps to being more productive at work, according to Clear:

1. At the end of each work day, write down the six most important things you need to accomplish tomorrow. Do not write down more than six tasks.

2. Prioritize those six items in order of their true importance.

3. When you arrive at work tomorrow, concentrate only on the first task. Work until the first task is finished before moving on to the second task.

4. Approach the rest of your list in the same fashion. At the end of the day, move any unfinished items to a new list of six tasks for the following day.

5. Repeat this process every working day.

That's it. Just write down your most important six tasks. You probably aren't going to get much more than six major things done in a day, so there's no use weighing your mind down with long-shot hopes that you might finally get started on that project that's not due for another three months.

Lee's advice was initially tailored toward executives, but it works down the corporate ladder just as well. You may need to pause your single-tasking when your boss gives you a last-minute job that needs to be completed ASAP, but essentially, Lee is just encouraging you to prioritize and give your full attention to what's most pressing, rather than cluttering your to-do list with an intimidating laundry list of things you know you won't really get done.

There's plenty of research to back up his insistence on concentrating on one thing at a time, too. Psychology studies have found that trying to multitask is pretty counterproductive. People who try to switch between tasks at a rapid clip make more errors and take more time than those who focus on getting one job done before moving on to the next.

Want to be even more of a superstar at work? Try not just writing down your tasks, but assigning them a time in your schedule—it might even help you get home earlier.

[h/t Fast Company]

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