Go to Dashboard > Session Control. In the header, click on your email, and click on My Profile.
Under Days Off section, click on the Add Day Off button and you’ll see several new options. Enter a day off name, a date or range of dates and check if you want this day off to repeat yearly. Click Add Day Off to add the entry. Depending on whether it is a repeating one or a one-time day off it will be colored in orange or red as shown on the screen capture below. Click Save Changes to save your entries.