How many things are you trying to remember right now? Maybe it's the email you still need to respond to, the appointment you need to schedule, the bill that's due Friday, the project deadline coming up next week, and the friend you promised you'd call. And just when you think you've got it all under control, something else pops into your head.
When you're mentally overloaded, you might start looking for ways to get everything out of your head. Maybe you've tried a notes app, an AI app, or even a personal knowledge management system, but all the options sound too complex to maintain.
That's probably how you ended up here. You were looking for a way to remember less, and somewhere along the way, “second brain” popped up.
If that sounds familiar, you're in the right place. Let's make this simple. You need a reliable place to put the things you're trying to remember and a way to make sure they come back to you when you actually need them.
The good news? Your calendar might be the answer you've been looking for. Here's how to use it as a simple second brain and take some of that mental load off your mind.
What is a second brain?
A second brain is a system you use to store and organize useful information outside your head. Instead of trying to remember everything yourself, you capture information somewhere you can easily find and use it later.
The idea became popular through productivity expert Tiago Forte and his Building a Second Brain method. The basic idea is that your brain is great at thinking, creating, and solving problems, but it isn't designed to reliably store every piece of information you come across.
Think about how much information you encounter in a single day. You might remember some of it, forget some of it, and spend time searching for something you know you saw somewhere.
A second brain gives that information a home. Instead of asking yourself, “Where did I see that?” or “What was that idea I had last week?”, you have an external place to capture and retrieve things that matter to you.
What should you put in a second brain?
That doesn't mean you need to save everything. In fact, trying to capture everything can make your second brain more work than it's worth.
A good rule is to save information that is:
- Useful: Something you expect to use for a project, decision, or task.
- Important: Information you don't want to risk forgetting.
- Interesting: An idea, insight, or resource you may want to revisit.
- Reusable: Something that could help you again in the future.
For example, if you're planning a trip, you might save a restaurant recommendation, a list of places to visit, or your flight information. If you're working on a project, you might save research, meeting notes, or ideas that you'll need later.
You don't need to save every article you read or every thought you have. The point is to reduce the amount your brain has to hold onto, not create another place where you have to organize endless information.
What makes something a second brain?
A second brain doesn't have to follow a specific format or live in a particular app. What matters is what the system helps you do. At its core, a second brain should:
- Get information out of your head: You should be able to capture useful information, ideas, or commitments instead of relying on your memory.
- Keep things organized: Information should have a logical place so you can find it when you need it.
- Help you retrieve information: A second brain is only useful if you can actually find what you've saved.
- Reduce mental load: The system should make it easier to remember and manage things.
- Help you take action: The information you save should help you make decisions, complete tasks or follow through on commitments.
- Be easy to access: If you can't get to your information when you need it, you're more likely to fall back on your memory.
Why your calendar can be a second brain
Most explanations of a second brain focus on storing notes and other information. But there's another category of information you’re constantly trying to keep track of: what you need to do and when you need to do it.
Your calendar can act as a second brain for exactly that.Think about everything you try to remember throughout the day. These commitments may not belong in a notes database, but they still take up space in your head. A calendar gives those commitments a place to live.
Your calendar is already a habit
One of the biggest advantages of using your calendar as a second brain is that you probably don't have to create a new habit. You already check your calendar to see what's happening today or plan your week.
Compare that with building a completely new productivity system. Your calendar doesn't require that same learning curve. It's already part of how you manage your time.
Use recurring events for recurring responsibilities
If something happens regularly, you shouldn't have to remember to add it to your calendar every time. Recurring events can handle things like monthly bills, weekly check-ins, quarterly deadlines, or other responsibilities that happen on a regular schedule. Set them once, and your calendar can continue reminding you when they're due.
Expert tip: In Calendars by Readdle, use recurring events and reminders to offload anything you repeatedly have to remember. Once they're set up, your calendar can keep track of the next occurrence for you.
This is one of the simplest ways to reduce mental load. Don't use your memory to remember something that can be automated.
Make capturing commitments quick
A second brain only works if you're willing to use it. If adding something to your calendar takes too many steps, you're more likely to think, “I'll add it later,” and then forget. That's why quick capture matters. Being able to add a commitment as soon as you think of it, without stopping to fill out multiple fields, makes your calendar much easier to maintain.
Expert tip: Calendars has natural-language event creation, you can type an event the way you'd say it instead of manually filling out each field. For example, type “Remind me to follow up with Alex next Thursday at 10 AM,” and your calendar can turn that into an event without the extra setup.
Keep your second brain accessible
A second brain is only useful if you can access it when you need it. If an important commitment is sitting on one device or trapped in a system you can't easily check, you're back to relying on your memory.
Your calendar should be available across the devices you use throughout the day. Whether you're checking your schedule from your phone, computer, or another device, your commitments stay connected.
Less to remember. More room to think. Download Calendars by Readdle and make your calendar your second brain.
