Static grass is made of small pieces of polyester fibres. It comes in many different colors, but the most common are greens and browns. I've used this stuff on bases for both my armor and aircraft models.
I simply sprinkle it on over white glue-soaked dirt. (Real dirt!) I always put way more on than is needed. Then I blow over the surface of the base and this does two things. It will remove the excess material (make sure you blow into a container so you don't lose all of this excess stuff) and it will make what's left stand up.
When it's all dry, I then paint it a dark green. Then I drybrush successive coats of lighter greens, yellows and browns. Then I finish it off with some washes of Rustall Black as well as some homemade stuff. (The recipe is top-secret!
)
Follow ups with some touch-up drybrushing may be neccessary, but that's about it.
In conclusion, I shall finish by ending.
Fade to Black...