Don't waste your time and money buying dessicant. There is no short cut. Air drying is the best Heat is BAD!!!!!
They don't keep produciing Psilicybin after they are picked.
I just pick them and put them on a bakers rack in my grow room in 2-3 days they ready to go. Of course this time of year the humidity is relativly low.
As far as cleaning just scrape the crap off. As far as drying them unless you're going to store them they don't need to be cracker dry. In fact the fresher the more potent, personally I prefer them kind of leathery, but its a matter of taste. Have fun and trip balls!!!!!!