To schedule a meeting with other Exchange users based on their availability, click New Meeting on the Home tab of the Calendar, or New Items > Meeting on the Home tab in any other folder.
This will open the Meeting Request window:
Fill in the meeting attendees, the subject of the meeting, the location if desired, and the start and end time and date for the meeting:
If you would like to reserve a room, click the "Rooms" button.
When the room has been located in the list, double click it and click OK.
Click the Scheduling Assistant button on the ribbon to view the availability of attendees and the room in one view.
You can click and drag an area on the grid to set a time for the meeting:
You can also click the Requirement column to choose whether this attendee will be required, optional, or just a resource (such as a room):
To toggle back to the appointment view, click Appointment in the Show group of the Meeting tab. Click "Send" to send meeting invite.