Cut a slit in the duct tape just below the metal square so that the copper strip can fit through and then attach as shown.
Stick the copper metal tape to the aluminum square of tape. Then fold the copper tape and tape the top of the copper tape to the duct tape on the back.
Use duck tape to tape your switch together.
Test your switch. Connect an LED so that the positive (long lead) is connected to the positive side of the battery. Then connect the other lead to one side or your button. Connect the other side of your button to the negative side of the battery. When you push in the center of your switch, the LED should light up!