I make a marinade with plenty of fresh lemon juice, oregano, salt, pepper, and garlic. I brush it on the meat and let it sit overnight. The day of cooking, I brush the mixture on the lamb every thirty minutes or so while it is cooking. This marinade works whether you bake, grill, or roast it on a spit.
What I do for my leg of Lamb is cut slits and stuff it with cloves of garlic, Greek Seasoning Cavender's, fresh greek oregano , black ground pepper, I don't salt because Greek Seasoning has enough in it. Then after I rub the leg of lamb with Olive oil and herbs and fresh Lemon Juice. Let Lamb marinate until the next day. Now be sure and take the Leg out and let it sit on the counter until room temperature before roasting or putting it on the grill. Cook until the internal temperature of the leg of lamb is 145 or 165 if you prefer. Serve with Greek potatoes and greek salad.