How do you get your ideas?

How do you get your ideas when your coming up with graphics? Do you have to do a lot of brainstorming or does it come to you right away naturally? I think it would take me awhile before I come up with a great idea for a design. That is how I work.

It depends. Sometimes I'm full of ideas and there are periods when a huge block comes and I can't seem to get out of it.
Actually anything can impress me, sometimes ideas just come like a lightning without any brainstorming.