Hide Pivot Table Fields

To hide fields, do the following:

Right-click on an empty space within the header region, and select Show Field List from the context menu that opens:

The Customization Form that provides access to hidden fields will be displayed:

Drag a field away from the header panel, until the cursor changes its image to the big 'X'. Then, drop the header:

or Drag and drop a field onto the Customization Form: