I saw in default gnome theme icons when I clicked right the mouse. The icons are very useful for orientation in the menu.
See the picture below. How can I add some icons to standard ubuntu theme?
If there no icon pack how can I add my own icons?
You can enable this option (It's disabled by default) in the configuration manager. This should be available through Applications -> System Tools -> Configuration Manager (The System Tools menu may be hidden - you can make it visible by going to System -> Preferences -> Main Menu and selecting the checkbox next to System Tools, and possibly the one next to Configuration Editor in side the System Tools menu). Alternatively you can run
You'll need to navigate to desktop -> gnome -> interface
If you want the quick one liner you can enter the following in your terminal
This is the outcome