There are a few specific steps you can take to keep a fully cooked ham from drying out while it's baking... - Like I mentioned above, save ham juices from packaging, and pour them into the bottom of the pan; this will help your ham to stay moist. - You can put a little less than a cup of water or some kind of stock/broth in the bottom of the pan before baking if you want. This will also add moisture. - Covering your ham with foil helps it to retain moisture, as well. Of course, you can also bake it in a roasting bag.