As mentioned, the + and - symbols are for LED's and if you want to them to work, they need to have their polarity respected. Essentially the + is the positive signal and the - is ground. You won't damage the case LED's if you have them connected backwards, they just won't work correctly. The switch and reset buttons don't matter which way they go, this is just a contact switch and it doesn't matter which side of the switch is connected to the pins.