Re: indicator-applet style .. toolbar icons have no colours
There's not anything inherent in the panel or the indicators that makes the icons grey; it's actually just part of the default Ubuntu icon style.
Load a new set of icons into Gnome (the gnome-look.org website will help you find some, and Gnome Tweak Tool will help you enable one) and they'll appear as intended. Colourful, if that's how they appear in the icon theme.
I try to treat the cause, not the symptom. I avoid the terminal in instructions, unless it's easier or necessary. My instructions will work within the Ubuntu system, instead of breaking or subverting it. Those are the three guarantees to the helpee.