Switch to the perspective that you want to configure.
Select Window > Customize Perspective....
Open the Menu Visibility or Tool Bar Visibility tab.
Find the item you want to hide. You can do this two ways:
Expand the menu or toolbar hierarchy to find the item you want to hide.
Click the Filter by command group check box to see a list of command groups which contribute items, and choose the command group the item you wish to hide. Then navigate to the item in the hierarchy in the Structure tree.
Hover over the item to get additional information:
a description of what the item does
the name of the command group which contributes the item (click the link in this item to switch to the Command Groups Availability tab with the appropriate command group selected).
any key bindings associated with the command the item performs (click the link in this item to open the Keys page of the Preferences dialog with the command selected, if possible).
if the item is dynamic, a preview of its current appearance (dynamic items are listed as [Dynamic]).
Uncheck the check box next to the item. Uncheck a menu to hide all its children.