You can alter the display within an individual toolbar to keep just the tools you need available with a minimum of wasted space. You can also show and hide tool labels.
Reader includes more tools and more toolbars than the set that appears by default. You can customize the toolbars so that the tools you use most often appear in the toolbar area.
Right-click/Control-click the toolbar, and select a tool that you want to display or deselect a tool that is already displayed if you want to hide it.
Right-click/Control-click any toolbar and choose More Tools. Then select individual tools and toolbars that you want to display, and deselect those that you want to hide.
The default view shows labels for some toolbar buttons. You can show labels for all buttons to help you as you learn to use Reader, or you can hide all tool labels to save space in the toolbar area.