Someone asked me not too long ago where I get ideas from. As I was trying to explain this intangible thing, the beginning of the creative process, I realized that it perhaps isn't that mysterious after all. Ideas come from inspiration. And I find inspiration in three ways: stubbornly, consciously, and subconsciously.
1. Stubbornly: Honestly, sometimes I don't have ideas. One of the most intimidating things is receiving a creative brief and not knowing where to start. It is an indisputable fact that the hardest part of anything is starting, and all the more so when you're drawing a blank. But sometimes the simple act of putting pen to paper is enough, because seeing just one line will give you an idea of how to proceed with another line, and so on. Making really does make ideas.
2. Consciously: Of course, designers don't work in a vacuum. I spend a significant amount of time perusing the Internet, learning about other designers, and curating an image library (although I know Pinterest is popular for this purpose, I'm a big fan of Tumblr). I also keep a so-called junk drawer for physical artifacts. I habitually file all of these things away physically, digitally, and mentally, to save them for later. Although I'm fully aware that it looks like a frivolous use of my time, this careful collecting and tagging, it has consistently paid off - sometimes in the most surprising ways.
3. Subconsciously: But sometimes you just need to walk away for a minute. No amount of staring at the paper or screen will produce the spark you need. Turn your brain off and let it percolate, then come back with fresh eyes.