are not that hard to replace, you just need to make sure that you do not break any more crawling on the roof. Before you start for saftey sake, make sure that you run a rope over the roof and tie off the end to something solid (not Car), tie the other end around your waist. There is usually 1 nail holding down the tile, You need to gently pry up the tiles above the broken tile...do not remove them just lift them up a little. Pull out the nail from the broken tile and remove the tile, Get some roof mastic in a caulking gun and squeeze out a bead on the upper side of the wooden cleat on the roof, Set in the new tile in place with the lip on the back of the tile over the wood cleat. Lower the upper tiles back down. Thats it!