As a game designer you need to keep searching for new and creative ideas to add to your games. Knowing where and how to find inspiration will help you significantly to create better games.
Have a work space where you’ll be either creating games or thinking about your games. It’s very important that it is clean, organized and that you have everything you need within your reach. Writting ideas down on a piece of paper may help get them flowing.
When you need inspiration, try looking at as many sources as possible. Movies, comics, games, books, biographies, photos or just about anything else. You can also try going out somewhere. To the park, mall or just taking a walk in the neighborhood can help.
There are many game developers that post much useful information in the internet. Find what other developers are doing in order to get their games done. The Game Design Developers page has lists of developers. Also, looking at work of people that are more talented than you can be inspiring.
Having a small project either as a side project or between big projects can help you unwind from the stress that big projects can sometimes cause. Studying a subject just for the fun of it can really add either variety to your routine or serve as a different source of inspiration.
Brainstorming is a great technique for coming up with new ideas. When brainstorming, try to be as creative and/or random as possible. Most ideas that you come up with won’t get into the game but some will usually kickstart new ideas that do end up in the game.
Here’s a list of resources that may inspire you: