If you want to only use the module without power there is no need to populate the resistors, leds and the power header. For Green as on put the long leg of you LED into the square hole.

Important: Absolutely make sure to use the 8x8mm Self Lock switches (they should have a blue pin where the switch cap goes on). Do not use the 8,5x8,5mm (white pin, black and grey body) as they have a different Pinout and will potentially damage your power supply. To make sure you have the right switches installed, check that there is no continuity between +12V and -12V in both switch positions before installing the module in your case.