Several formal Idea Generation (IG) methods can be found in the design literature ranging from simple methods like brainstorming to complex procedures such as synectics. Experimental evidence is needed to support claims regarding the effectiveness of these methods in promoting idea generation. This paper attempts to prescribe a method for evaluating intuitive idea generation methods. The set of guidelines for experimental evaluation include metrics, how to measure against those metrics (quality, quantity, novelty, variety), how to compute the results, and types of experiments to run. Statistically based Design of Experiments (DOE) principles are in developing the guidelines. Four classes of variables are considered. Two experiment methodologies are proposed. In the Direct Method experiments are conducted using the idea generation method in its entirety. In the Indirect Method, each idea generation method is decomposed into key components and its effectiveness is predicted by experimentally studying the effectiveness of its components and interactions between them.