One's creativity is enhanced only when it is used regularly. The more you tend to use it the more you train your self to look at things in different perspectives. The things we see around us are results of creative thinking that was, in most cases, initiated by combining old concepts and observations. Hence, our creativity is based on what already being created or at least thought of creating in the future.
Thinking inside a specific frame deprives you of endless streaks of thoughts, as you restrict your thinking into some extent. That explains why children have a great tendency of showing a wide range of thoughts and imaginations through their creative expressions, which happen to be simply amusing. In the creative thinking process it is advisable to avoid following a certain criteria or guidelines, in order to discover the portal to a higher realm of conception.
"Many ideas grow better when transplanted into another mind than in the one where they sprung up."
- Oliver Wendell Holmes