Ok the best way to dry your shrooms is buying slice cristals (on any chemistry store) this little cristals are blue and they turn pink when they have dryied ur mushrooms u can use them again but u have to put them in the sun or in your oven.U will have to buy more when they turn like red...
put the crystals in a little clothe bag or in a paper then put them in a plastic bag and put them in your freezer.