Using a guide would definitely help you, as the 3 numbers are different for everyone. The colours at the top of the numbers represent the order the numbers are in, like a blue 6 or a red 5.
My personal code is 505 but this wouldn't work for everyone. There really isn't anything in there other than a relic, an easter egg or present in those seasons or Simon during the anniversary hunt, which is why I'm assuming you're asking, due to something probably being in there.
