Simon Says Assembly Guide
Capacitors
Locate the two 0.1uF decoupling capacitors. These look a little different than resistors. They have two leads than come down off the bottom of the component, and they have the markings “104” on them. (also note, the bottom side may have some other letters, like “K5M”). They look like this:
Locate their positions on the PCB:
Insert the capacitors, flip the board over to the bottom side, and solder the pins just like the resistor.
Note: The decoupling capacitors help "clean up" the power on the board.