I consider myself well-coordinated, but I've had no such luck with couscous. Especially when transferring from the pot to another container. It decides to stick together, then randomly makes an avalanche as I'm scooping, creating a mess of grains from the countertop to the floor.
I mix some butter in it when it's done, mainly for taste but it also helps with the issue you described. And have you tried different grain sizes? I use different types depending on what I'm making alongside it and the bigger/coarser kind is easier to handle.
It depends how much I am making. A pint or a quart. I typically only make one or two servings at a time. I mostly eat it on salad, or with cucumbers and tomatoes.
It cooks quickly, so I only add very hot or boiling water (if I am using boiling water, I ensure the jar is preheated to avoid cracking) to the jar and let the residual heat cook it.