Out of Office message for Office 2013, Office 2010

1. Click the File tab, and then click the Info tab in the menu.
2. Click Automatic Replies (Out of Office).
3. From that box, select the Send Automatic Replies check box.
4. There you can select the time when you are out of office and there are also options to sending only for Inside my organization , type the message that you want to send within your organization, and  the Outside my organization for outside incoming emails.

That's all! :)