How come wind...

...isnt visible?

 

Because the wind was trained by the secret clan of ninja storm clouds called "the League of the Night Sky."

 

because youre not looking hard enough

 

Lol, it' s actually true. Ever wondered why space is black but the sky is blue ? Because air is blue, but we don' t notice unless there' s a lot of it.
As for tracking its movements in particular it' s just like with water : put stuff in it, it helps.

 

Watch the leaves.

 

Spoiler: Because you lack the proper visor for your Power Suit.

 

If light travels so fast, how come it's never caught the wind?

 

Because it is trying to get it to notice her first.

 

If you can't see the colors of the wind how can you paint with them?