If there is ever a period of a day where you're not going to be able to take appointments (maybe you have your own doctor's appointment or you have to go to your daughter's soccer game or you just need 15 minutes of no appointments to meditate), you can use the Time Off feature to block part of your day off so no appointments can be set during that time. This may be faster than, say, going through and modifying your staff availability for the day.
In order to add Time Off for less than a day, go to Appointments and click on the purple "Add Time Off" button:
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