Fly fishing differs from all other fishing methods because it is the weight of the line that is used to cast the lure, instead of the weight of the lure, which can be very tiny. If learning how to cast a dry fly, know that as with almost all fly casting, propelling an essentially weightless lure requires false casting to build some line momentum to then shoot the line forward.
The main difference regarding how to cast a dry fly versus a wet fly, might be in that the dry fly is the lightest of all light lures because it is designed to float on the surface instead of sinking flies which then can be heavier and may also be in tandem rigs. Therefore, dry fly casting techniques may have a tighter, more flattened loop during an overhead false cast, whereas a wet fly such as a beaded nymph or streamer will have a looser, open loop casting component prior to shooting.
The roll cast is a good beginner dry fly casting technique because there is no false casting. The downside is that casting distance if limited to the length of line you have out and can keep in control in a big, slow rolling flip. The good news is that you don’t have to worry about brush behind you which may grab your fly during the back casting of a false cast.
Because of the visual anticipation, the surface bite usually is regarded as the most exciting hit. Once you have learned how to cast a dry fly some distance, you can begin to hone your skills with fly selection, casting placement, and mending the line for the “right” drift. When you pick up your fishing license, there may be regulations available which often provide areas specifically for fly fishing too.