A jigsaw's thin, reciprocating blade easily creates curvy and linear cuts through ceramic tile, particularly tile that's already installed. The key to cutting ceramic tile with a jigsaw is to use an abrasive, mineral-grit coated blade; a toothed blade will shatter the tile's glaze. Abrasive jigsaw blades are coated with either diamond or carbide grit and they're often marketed as "tile-cutting" blades. With the right blade attached to your jigsaw you can cut oblong holes, curves and patterns through ceramic tiles.
Draw the shape or line of your cut on the tile's surface with a pencil. Attach a tile drill bit to a power drill. Place the bit's tip near the interior edge of the pencil line or shape. Activate the drill and drill a hole through the ceramic tile.
Attach a tile-cutting blade to the jigsaw. Insert the blade through the hole you drilled in the ceramic tile. Place the jigsaw's base plate flush against the tile's surface. Position the blade in the centre of the hole so that it will not contact the tile when you first activate the saw.
Pull the saw's trigger to activate the blade's motion. Slowly force the blade through the tile along the pencil line. Cut until you return the beginning point and allow the waste piece to fall from the tile.
Lay out the position of the cut line on the tile's surface with a pencil.
Attach a tile-cutting blade to the jigsaw. Place the saw's base plate against the tile's surface. Align the blade with the cut line. Pull the blade away from the tile's edge so that the blade does not contact the tile when you turn on the saw.
Pull the saw's trigger to activate the blade. Firmly push the blade into the tile. Push the saw blade through the tile along the cut line.
If you are attempting to cut a perfect circle, consider purchasing a cylindrical tile hole saw specifically for the project; hole saws attach to average power drills and are available in precise diameters.
Wear safety goggles to protect your eyes from flying tile shards.