If you've never made clams oreganata, don't be intimidated. They're not difficult to put together, and they can be made an hour ahead and heated up last minute. While you can certainly shuck them, I prefer to steam them just until they open and then dress them, just to make it a little bit easier on myself.
The one thing you should do is use real breadcrumbs rather than the kind out of the box. To make them, cut the crusts off of a loaf of Italian white bread (something soft inside) and cut it into thick slices. Place them on a baking sheet (no oil or butter necessary) and place them in a 275 degree oven just until they dry out. Pulse them in a food processor, and store them in a plastic bag in the freezer until ready to use.
3/4 cup homemade dried breadcrumbs
2 tablespoons freshly minced parsley
1 teaspoon freshly minced oregano (or 1/4 teaspoon dried)
1 clove of garlic, minced
2 tablespoons olive oil
Juice of 1/2 a lemon
For the breadcrumbs, combine the breadcrumbs, parsley, oregano, garlic and olive oil in a small bowl and stir until the breadcrumbs are moistened. Set aside.
Scrub the clams well in order to remove any sand from the shells. Place the clams in a saucepan with a little bit of water and cover them. Steam them just until they're open, 2-5 minutes. Set aside.
When the clams are cool enough to handle, split the shells in half and loosen the clam with a spoon so they're just sitting in the shell (and no longer attached to it). Dress the clams with a few pinches of the breadcrumb mixture. Clams can be prepared to this point and chilled for one hour.
Preheat the broiler, drizzle the clams with a bit more olive oil (if desired) broil the clams until browned.
Squeeze the lemon juice over the warm clams and serve.