The game design phase covers many areas and sets the groundwork for the rest of the game making process. Start by writing down all your ideas in the Game Design document.
Define your game idea in more detail. The story, gameplay mechanics, fun factor, a list of assets to build, and a development schedule are just a few aspects to consider.
Create concept art to visually establish and communicate the look and feel of your game, so 3D artists can build it and give it life.
Tell the story of your game. It might be simple or highly complex, but knowing your story will guide many other design decisions.
The Game Design Document contains things like the game’s story, concept art, gameplay mechanics, a list of assets to build, a development schedule, and a lot more. You also need to make concept art for your characters and environments so you know how you want things to look, and to share with your team.
Drawing your ideas for a game is one of the most important steps to eventually having something playable. And Sketchbook is probably the easiest way to get started. If you’ve used a pencil, you can use Sketchbook.