Click the "Settings" button on the right hand side just above the listed members and click the moderators tab on the left hand side. Click "+ Add New" and begin typing the name of the desired moderator. Keep in mind any moderator must first be a member of the community. If they have not yet joined you must invite them before granting moderator status. If they are already a member, click their name in the drop down menu and press "Add". 

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