Mac: Do Not Disturb is great on a Mac, but it doesn't really quiet down everything. If you want to set Do Not Disturb to run on a schedule alongside disabling your volume, WonderHowTo shows you how with an Automator app.
The Automator apps here are created by Lifehacker alum Adam Dachis, and they're pretty simple to use. Once you download the files, you can enable or disable quiet time with just a click. Alternatively, you can create a calendar event to run them on a schedule. Unlike setting up Do Not Disturb to run on a schedule, you get a little more control here over which days these scripts run, and you get the added benefit of muting your Mac entirely. Head over to WonderHowTo for the full guide and downloads.