The Bentonite is difficult to mix, you have to add little amounts of water until you get a paste. Then keep mixing until you get the lumps out. Then add water a little at a time until it gets to a smooth yoghurt consistancy. I use a hand blender, but it's a plastic mixing head - you shouldn't use metal. I still have to make it into a paste first though. I grab a handful and sort of scrape it onto my skin with my fingers, pressing it on. I make up a batch and keep it in a plastic bag in the bathroom. I havent tried the whole body mask yet, I dont have enough energy to mix that much clay.
The thing is to keep it wet while on the skin, it's not effective once dry and it actually hurts my skin when it dries and leaves it very red.