Hi dearsanta,
you have to follow the line of the drawings next to the buttons.

Every drawing has two ends:
- one with a square (WS), the entrance;
- one without square (WOS), the exit.

Starting from the top left drawing, the WOS exits in the bottom right angle.
This must be connected to the WS of the second right drawing from top (because here the square is depicted in the bottom left angle).

Follow the line and the WOS exits in the middle left side.
This must be connected to the WS of the second left drawing from bottom (because here the square is depicted in the middle right side).
And so on.

I don't know if I've been clear.