It must be hot, dry and breezy. For most of us, it is not an option. Indoors, a food dehydrator is recommended and the most convenient method of drying. There are many types on the market in varying price ranges. Microwaves are recommended only for herbs since adequate air circulation is not possible.
Most user manuals provide instructions.
Herbs can also be hung to dry in a well-ventilated room. Selection of foods for drying is the same as for any preservation method. Fruits should be ripe, but firm. Vegetables should be very fresh. Clean and peel as usual.