It is important to plan your tiling properly. It is unlikely that the floor will be exactly the right width and length that you will not have to cut any tiles, so planning will help you decide where cut tiles will be needed and to what size they need to be cut. Lay a cross shape of full sized, uncut tiles from one end of the room to the other. This will give you an idea of how many tiles you will need, and will help you decide where the cut tiles should go. You will want the cut tiles to have as little visual impact as possible so consider where the light comes in from a window or the positioning of the bath, toilet and cupboards.
Tip: A number of different tools can be used to cut tiles, including a scoring cutter, diamond tipped saw blade, tile nippers or a handheld grinder.