Is this something that you do and do you feed it daily or how do you go about feeding the grass?
I haven't really done it since we moved to our new place, since there isn't much grass here. But at our last house we had a huge front yard with really beautiful green grass, and dandelion greens and plaintain, and I would pick a bunch of it. Then just fill the blender about halfway with water, and start adding the greens. My vet also said to throw in some vegies and fruits occasionally (for extra nutrients), so we used carrots and apples and cucumbers. Blend a little at a time or else the grass will get caught in the blades. Once it's nice and mushy like a green smoothie, I just pour it over the kibble, maybe about 1/2 cup for each dog at meals. Then you store the rest in a pitcher in the fridge. I don't think you have to give it at every meal, my vet seemed pretty casual about the whole thing and thought of it as a supplement.
My dogs LOVED it!!!
In fact, I need to find a patch of grass around here and start doing that again!