well, there is no secret to it, just know where is your light source is.
my own recipe to take dark pic is to have a steady hand or support and use auto shoot with no flash. this will increase your exposure but slower shutter speed, so u need a steady support. or you could try night mode too.
another tip is to use the action mode with no flash, this will allow faster shutter speed and easier with free hand.
well the real secret is to take alot and choose a good one after that, hahaha
also, none of my pictures are edited with anything, RAW!