My recipe for my vibratory tumbler is walnut shell lizard bedding, and approximately 1/2 teaspoon of mineral spirits, 1-2 teaspoons Nu-Finish car polish, and a couple chunks of dryer sheet or even paper towel with each batch. You can buy bigger bags of walnut cat litter, blasting media etc. for less, but I don't feel I personally go through it fast enough to warrant storing the bigger bag.
Start the tumbler, pour the wet components in slowly spreading them out to minimize clumping. let in run a few seconds to spread out and mix in, and then add my brass and dryer sheets. If you dump brass first you occasionally get clumps of media stuck in the necks from the wet stuff.
Cleans about as well as can be expected for dry/vibratory tumbling, and leaves very minimal dust if any.