If you aren't a professional, it's likely that you aren't frequently working with tile
Penciling It In
For simple, straight ceramic tile cuts, a carbide-tipped pencil does the trick. It's not the best way to cut tiles, and this method might get tiring for large-scale tile jobs, but it comes in handy for basic DIY projects. Grab a carbide-tipped pencil and a straightedge, such as a speed square, from your local hardware store. Place the tile on a stable, flat cutting surface. Position your straightedge as desired, and hold it securely in place, applying ample pressure. With moderate downward pressure, drag the carbide-tipped pencil along the straightedge, across the length of the tile, to make your cut. Quickly repeat the cut, making a few drags across the tile, to create a scored line. Once that's done, turn the pencil around and fit the scored edge of the tile into the attached clamp. Hold the tile tightly with your other hand and press the pencil downward to snap off the scored part of the tile, or use tile nippers as a stronger alternative if one's handy. You can then sand the edge smooth with a medium-grit rubbing stone. This will work for ceramic tile specifically, but other types of tile and flooring – including brick, cement, terra-cotta and porcelain – will require a wet saw.
Advanced Tile Cutting Tools
For larger jobs, or situations in which you have to create notches