Me and my dad did this the other day you have to pull the old tile off and lay then ones down.you have to measure the floor and the tiles .
How Do I Install Tile Around My Bath Tub?
Here is a tile install guide. Read over it and see what you can and can't do. Sometimes its best to leave it to the pro's but I think you can do it! :) www.findanyfloor.com HAVE FUN! I hope that link helps?!??!!