This document shows how to change the permissions of a certain folder to allow others access to its contents. The following instructions are for Microsoft Outlook 2010.
Open Outlook 2011 and click on the folder you would like to share and then click the Permissions icon.
In the Search textbox type the name of the person you wish to give permissions to.
Select the name of the person from the list and click Add ->, then OK.
With the correct name selected, click the boxes to allow amount of access you would like the person you are sharing permissions with to have and click Apply, then OK.
Your new settings will be applied and folder will be shared.