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Select calendar from the list of available apps.
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Select New and then Calendar event.
Tip: You can start entering meeting information on the Details screen, or wait until you've finished with the Scheduling Assistant.
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Type the names of people you want to invite in the Attendees box. This box works just like the To line in a new message. Outlook on the web will search for matches as you type. If no match is found, or the matches returned aren't correct, you can search for attendees.
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Each person you add will automatically be added as Required. To change that status, right-click the name or, if you're using a touch device, touch and hold the name, and then select Attendance optional. As you add people, you'll see a count of the total number of people invited and how many conflicts there are.
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Choose a location. You can select Add a room at the bottom of the Scheduling Assistant to see conference rooms from your organization's address list. Choose available rooms that begin with SVC if your meeting is held on the 3rd floor of SVC.
After you've selected a room, it will be added to the calendar grid.
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You can change the conference room by selecting Change room. 
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Click All apps.
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Click Calendar.
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Click New event.
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Fill in the fields.
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Select the date and time. The window will indicate red if one of the attendees has a conflict and green is everyone is available.
Click Send.
As you add attendees and a location, their calendar information will appear in the calendar grid. You can select day or week view at the top of the calendar. If you select week view, the calendar grid will show a merged view of the attendees' calendars.
Tip: In week view, you can hover over a block of time to see more information about conflicts at that time.
Click OK to save your changes or Discard to cancel.
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