Erick nailed it. Shoot what you're comfortable with. And all too often, more rounds can mean mistakes getting grooved in and flinches built.
However,handle your shotgun frequently, not every other weekend. With it KNOWN TO BE EMPTY, of course. Mount it and swing it a few times every day. Have a friend who reloads make you up some dummy rounds, with shot and wad, heavily crimped, but no powder nor primer, and use those to practice loading,unloading,and so on. I suggest using trash hulls way different than your normal loads, like those orange or pink Fiocchis.
Handle your shotgun until it feels natural, shoot it a comfortable amount and use good form. Then one day soon a clay will explode in front of you, you'll note that so did the last 20 or so and it feels as natural as breathing. Or, depending on where you're going with this, you deal swift and certain death to a Q/Tombstone/bowling pin target and realize you're now dangerous to only the right people....