Make a 'Personal Podcast' When You Study

Memory is a tricky thing. Scientists have figured out how many units of information you can store in your short-term memory (around seven, though there are great workarounds for remembering more than that), but if you really want to remember something, you have to go over it a bunch of times until it lodges deep in your brain.

If you're getting ready for a test at school or a presentation at work, you probably feel like you don't have time to go over the content again and again and again--but you do, if you make a personal podcast.

How to make a "podcast" to help you study

Next time you want to really retain the details of something you're studying, open up the voice notes feature on your phone, because you're going to make yourself a little study podcast. Obviously, you could just read your notes out loud into the mic; it's the simplest option, and a good one. (If you're memorizing a speech, just perform the whole thing.)
You do have others, though. You can record separate "episodes" for each mini-topic you're studying, which will help you organize your thinking and provide an easy way to focus if you need brushing up in a particular area.
You don't have to worry about the thing actually being pleasant for others to listen to, so make it useful for your own study style. The U.S. Army suggests asking yourself review questions, pausing to give yourself time for an answer, and then going ahead and stating the right answer for the record. Over on Reddit, users suggest reading passages from textbooks into the mic or roleplaying as the professor and "teaching" off the cuff.

The most important part comes after you've recorded your personal podcast: You have to listen to it. You have to listen to it a lot. Play it through the speakers of your car or through your headphones on the train to make your commute productive. Play it at the grocery store, when you're doing errands around the house, and when you are relaxing at night. Fall asleep listening to it.

Why it works

Picking things up from your personal podcast is an example of rote learning, the process by which we memorize things based on repetition. But it has other advantages, too.
For instance, even when you're compiling the notes and deciding what to include in the mini podcast, you're studying--you're making decisions about which concepts are most important, how they flow together, and how you can present your mastery of them to others.
Reading is all well and good, but you remember things better when you process them in a variety of ways. Organizing your notes, speaking them aloud, and listening to them read back to you: All will help you more thoroughly process and recall the content. Each of those is commonly used on its own as a standalone study technique, so imagine how effective they'll be together.