Many of us, myself included, do better when we brainstorm with others. The shared energy and shared ideas all feed off each other to create something new. Let's create an imaginary scenario here of the creation of a business logo.
Most of us have a community of some sort, whether business associates, employees, friends who understand our work, or like-minded network members. Gather everyone together, in person or by phone.
Present the topic of discussion ("I'd like your input on a new company logo. I want it to ________. I do not want it to _______. Let's discuss!") You may want to make it clear that all opinions are welcome without judgment.
You'll get a variety of opinions, some voiced more assertively than others - make note of all the ideas. One person's comment may seem off base, but an idea generated from it by someone else in the room works well for you. That's the value of brainstorming!
When the topic seems to have been sufficiently gone over, I always recommend stepping away from the project for a day or two. With fresh eyes, go back over your notes, and see what ideas jump out at you. Sometimes the right answer seems obvious after this exercise, and sometimes more discussion will help.
Don't go it alone - brainstorm the answers!