Well, its entirely up to you, whether you want to have it crisp or soft and juicy. I am sure you know how to apply all the salt and herbs. Keep it for 2-3 hours for marination. Then if you want to have it crisp cook it on low heat on the pot for 1-1/2 hours. You wont need any water for cooking this way. After it is cooked on the pot, keep it in the oven for 15 minutes on medium heat. If you want it soft just cook it on the pot for 2 hours in the same manner. Then put a little oil and fry it for 15 minutes.
Love leg of lamb! Here how I would make it .If you have a rack for your pan I would place that in the bottom of your pan and place your lamb on top of the rack. Turn your oven on 400 and wash the leg of lamb and dry it with paper towel then rub it down with olive oil and rub with garlic and rosemary(meduim amounts).Cook at 400 until the leg is nicely seared (golden brown color ).Then turn your oven down to 350 and cover leg with foil or if you have a cover for your roasting pan and finish cooking until your desired temp usually 160 to 170 internal temp.