The Game Design Document (GDD) is critically important. It’s basically a written version of your game. It discusses rules, mechanics, characters, worlds, weapons and more. Designers write GDDs in advance of development to describe the game they want to make. The GDD must be proofread by team members, friends and family, investors, pets, and anybody whose opinion truly matters for turning ideas into reality- including yourself. It’s easy to get out of bed intending to write a good GDD later, but it’s actually much harder to achieve that intention. This is because writing an effective GDD is difficult. Not surprising. Expressing ideas is difficult generally. Have you identified your core concepts? Are these presented appropriately? Do you understand your audience? These are important types of questions. Thankfully, you can answer them all and lots more with our comprehensive online guide to creating Game Design Documents. – Alan ThornDon't be the game designer writing only for themselves. That's a sorry place to be. You have important ideas worth hearing, so communicate them well or not at all