Just about everything in a game can be changed, from the look and dress of the characters to the colour of the sky, the design of the world, and the sounds and music.

Modding – an abbreviation of modifying – involves taking an existing game and altering its content. Indie gaming is the plucky youngster of game design, and stand-out games like Braid and Minecraft are often developed by one-man coding powerhouses. Modding is a tried and tested route, and a handful of big-budget titles and large studios began their illustrious lives as humble-but-brilliant add-ons developed by a handful of people. There are, essentially, two ways for budding game designers to get started in the field of game design. We've used Valve's Source SDK to present an overview of what's needed to create a game, as well as detailing other engines and game creation programs. Our aim here isn't to show you the finer points of coding your first triple-A title, it's merely to show you the tools available for game construction. Valve's Source SDK is a great place to start, but on top of that you've got the Unreal Development Kit, Skyrim's Creation Kit, Unity and Game Maker. The best thing about current games – and it's never been better – is that you probably already have the tools to make an entire game from scratch. Like so many creative industries now, it's become full of eager fans who are willing to work for free to have that chance at making it to the top, the chance of becoming the next Ken Levine or Gabe Newell. The modding community is still huge, still adding new content to games and correcting the mistakes original developers made. Not everyone wants to construct a complete game, though.

This way, those crucial themes are never lost and the narrative never strays from its original path. The technique's not unique to games – the best novels, films, music and art start out as a simple, broad stroke that's layered and built upon until you've got a finished product. Everything can be expanded from this point onwards, but it's important to always come back to that original point.

How to create your own game character