Click on the "..." button situated at the top right corner of a day, then click "make rest day" from the pop-up options window. This action will mark the day as a rest day, with the label "rest day" displayed.

If you already include some workouts in a day, you can still make the day as a rest day, by the similar process mentioned above.

After a day turned into a rest day, when you click the “…” button situated at the top right corner of the day, a “cancel rest day” option will be shown in the pop up option menu. Click on it, your day will be recovered to a normal day.

❗ If you already include some workouts in a day, and make the day a rest day, when you cancel rest day, the original included workouts will be gone.