Speed reading is a skill that can be hard to master. There are a ton of books, talks, and articles dedicated to teaching people the “right” way to learn the skill. This week, Fast Company spoke to one of those experts who wrote a book on topic to get some quick and dirty tips on how to learn. One of her suggestions: use an index card.

The idea behind this is pretty simple. Whenever you’re reading physical media such as a book or newspaper, put a white index card above the sentence you’re reading. Placing the card under what you’re reading blocks out everything below it and helps your mind focus on the sentence you’re trying to process right now.

While many people who try this trick put the card under what they’re reading, the expert argued that leaving what you’ve already read exposed will encourage you to go back and re-read that portion. Putting the card above blocks out what you’ve already done and keeps you focused on where you’re going, not where you’ve been. It also pushes your eyes down the page.

For online text, you can do something similar, by always reading documents from the very top of your browser window. As you go, scroll so that the portion of the page you’ve read disappears from sight.

The trick also doesn’t have to be an index card. I do something similar with bookmarks and get a similar result. It also keeps me focused on where I am in reading something, so when that inevitable interruption comes and can pick up reading where I left off.