I washed the leaves, put them on a paper towel, and microwaved them for about a minute, I guess, in 30 second intervals. (I don't remember exactly.)
I let the oven cool some, and then I laid the paper towel and leaves in the oven and just left them overnight.
The leaves are nice and dry. I put them in a plastic zip bag. I will probably just rub them in my hands to crush them. If I had a larger quantity, I would probably use the blender to grind them.
Now, I just need to find a suitable gumbo recipe.