To add a tool button to a toolbar, right-click on the toolbar and choose New Button. 

The toolbar "owns" the tool button, so moving or hiding the toolbar also moves or hides the button. In addition, all tool buttons on the toolbar automatically maintain the same height and width. You can drop other controls from the Tool palette onto the toolbar, and they will automatically maintain a uniform height. Controls will also wrap around and start a new row when they do not fit horizontally on the toolbar.