Looks like a river. Mirrored Furniture DIY - Measure and cut mirrors w/ a glass cutter (score and snap the pieces off) Apply mirror mastic to the back of the mirror pieces and press them firmly onto the furniture piece. Do large pieces first. Clean with acetone to remove all the excess mirror mastic. Apply grout to soften jagged edges and fill in any tiny gaps you may have. Remove the extra grout with a damp cloth.