Keep your Netbeans environment clear of clutter by only allowing a set amount of tabs to be open at any one time. To set the number of tabs permitted go to:
Tools->Options->Editor->Maximum Opened Tabs
To streamline your IDE even further it is recommended to also use an Autosave plugin such as http://plugins.netbeans.org/plugin/37077/autosave-module-for-6-9-and-later