The majority of solder paste is applied by way of stencil printing. In this process shown here, a metal stencil with apertures cut in it where the paste can pass through is placed on top of the PCB such that the apertures match up with the metal pads on the PCB. A bead of solder paste is then moved across the stencil filling the apertures. The stencil is then separated from the PCB to leave a deposit of solder paste on each pad.