SQWIB beat me to part of my method:
First of all, I use Yellow Mustard on Pork, and Worcestershire Thick on Beef. I want to try A1 soon too, but only on Beef.
Then I put whatever dry rub I'm going to use on top of that.
My Method:
First I lay out a big enough piece of plastic wrap on my counter, and smooth out all the wrinkles.
Then sprinkle a good amount of my rub on that sheet, in an area bigger around than the piece of meat I'm rubbing.
Then coat one side of the meat with whichever I mentioned above, and drop that piece of meat onto the rub I spread out on the plastic wrap, with the wet side down.
Then I coat the other side with the wet sauce, and be sure to get some on the edges of the meat too.
Then put the dry rub on the final side, including some on edges.
Then as I'm folding the plastic wrap up over the meat, I lift the plastic up smartly around the edges, to get the dry rub that is on the plastic wrap to fasten itself to the edges of the meat, instead of it sliding in on a pile.
Then finish wrapping.
Bear