The first step in creating a new game is to describe your world and how it works. The way you do this is with a Design Document, often referred to as a Bible. Here you put down as much information as you can muster. Laws of physics, geography, culture, legends, history…it all goes in here. Some or most of it may never be visible or directly apply to the game. It’s there so you know how to implement everything. The information directly influences the design, code, and gameplay.
The Deep Blue is to be a casual, browser-based game of sea piracy on an alien world. The first step to make it happen is its design document.