Your opening hours decide when customers can book. Set them once in Settings, then Opening hours: your normal week, closures like Christmas, and blocked time for a person's holiday or a van in the garage. If something is already booked when you block time, you see it first, with a fix.
Open Opening hours
Choose Settings, then Opening hours.
Set each day
Under Every week, set the opening and closing time for each day, or mark it Closed.
Save
Choose Save at the top. Your listing shows the same hours.
Under Closures, the public holidays for your country are listed ahead of time. For each one, choose Close that day or Stay open.
To close for something else, like a winter break, choose Add a closure. Give it a name, a first day and a last day, then choose Add closure. If anything is already booked on those days, you're shown it before anything changes.
Use blocked time for one person, one thing, or the whole business: a holiday, a training day, a vehicle being serviced.
Choose Block time
It's under Blocked time, on the same page.
Say who or what, and why
Under Who or what, pick a person, a room, kit or a vehicle, or Everyone (the whole business). Add a reason, like "Holiday".
Pick the dates
Choose From and Until, all day or between set times, then Continue.
If nothing is booked then, it's blocked straight away. If bookings already hold that time, you see each one with a suggested fix, like another team member at the same time, or moving it. Choose Block and apply the fixes, or Block now, fix later.
Team members who can change their own hours see Block time off on their My day screen. It opens this page.