Select Resources, select +New and from the menu select Content Bundle.
In the 'Properties' panel, enter the Content Bundle Title (required) and any other metadata that you feel is useful. Tip: You can select or edit other properties now or later. You can make properties as simple or detailed as required. Consider if the item is to be shared. This will help you determine the level of detail required.
Select Save. Now you can add resources to your Content Bundle.