A method for forming an electronic device including two stacked liquid crystal cells is disclosed. A first liquid crystal cell including two substrates is provided. A second liquid crystal cell is formed by disposing another substrate to one of the substrates of the first liquid crystal cell. Subsequently, a cutting step is performed to cut off unnecessary portions of the substrates of the first liquid crystal cell and the second liquid crystal cell. Before bonding the another substrate, a pre-cutting step is performed to form at least a pre-cutting mark on the substrate on which the another substrate is bonded in order to facilitate removal of unnecessary portions of the substrates.