This step is pretty self explanatory: clean the herb really, really well and then grind it up in the cannabis grinder. I use 2 bowls when doing this - one for stems and leaves, the other for the finished/ground herb powder.

My advice is to grind up the herb in small batches and then combine it into the mixing bowl as you go along. I use wooden toothpicks to clean the grinder, scooping the sticky trichomes into the bowl. If you don't clean it every 2-3 runs you will encounter problems.