In a world awash in information and data, picking the most useful pieces out of the moras is a critical skill for any productivity-focused individual. It doesn’t matter if it’s a medical journal on sepsis or a blog post by a writer you follow; it’s important to have a system to remember and organize everything you read.

Index cards are the ultimate flexible to-do list system.

I use index cards to stay on top of my most important activities. My system has changed over the years as I have learned more and improved about controlling my focus.

Here are three different versions of notecard systems that I have used over the years to stay on top of my most important items.

Version One: David Allen’s Getting Things Done methodology.

I first read this book in medical school. It changed how I approached “getting things done”

David Allen’s concept of getting everything out of the open mental loops in your head and on paper is a key concept to help prevent feeling overwhelmed and anxious. This point cannot be overstated.

Applying this to an index card system is as simple as putting all the open loops in your mind onto a list on your pack of notecards. Once it’s written down, you don’t have to waste any mental energy ruminating on the item.

Now you can focus on transforming all the ‘stuff’ you accumulated into a clear inventory of meaningful actions, projects, and usable information.

You can read more about applying David Allen’s Getting Things Done methodology in my 5 min book summary.

Benefit: Easy to do and get started, generates a simple list, easy to see everything that needs to be done in one place.

Weakness: Hard to prioritize, tend to focus on the items that are easily checked off the list, can lead to being busy but not necessarily productive.

Version Two: Gary Keller’s, The ONE Thing

Gary Keller’s The ONE thing concept is another great productivity system that works well with a notecard system. The system is designed around the focus question:

Put that ONE thing at the top of your list on the front of your notecard, and stay at that one thing until it is completed. When that one is done, you can add the next ONE thing below it.

To manage your open mental loops, keep the back of the notecard for the items you need to write down and get them out of your head.

“What’s the ONE Thing I can do such that by doing it everything else will be easier or unnecessary?”

The ONE thing

You can read more about Gary Keller’s The ONE Thing system in my 5 min book summary.

Benefits: Easy to understand. The focusing question helps address a major problem most individuals struggle with: not everything matters equally.

Weakness: We often have “One Thing” in different phases of our lives that are in conflict with each other. Personal vs. professional, etc… This context is difficult to represent on a notecard.

Version Three, The Eisenhower Matrix Methodology

For those unfamiliar with the Eisenhower Matrix, it’s also known as the.