The easiest way would be to put the baffle on a shim or slatted rack so all you have to do it take the hive off the bottom board, add the shim or rack and add the hive back on top. Without a shim you would have to put three pieces on the bottom board and one on the front of the bottom box. I think the bees might get upset with all the maneuvering and hammering on the front of the bottom hive body. There's a short video on their web site on putting the baffle on a hive that might help. You can order the baffles attached to a shim for a dollar or two more so it's ready to put on the hive.