In Konno et al.'s (in press) experiment of co-creation of artificial language, it has been confirmed that a formation pattern had three stages: the establishment of conventional behavior, symbol system and division of roles using turn-taking. However, forty percent of participants failed the formation. We consider that a cause of the failure lies in difficulty of separation among the three stages which demand learning at different levels. Thus we designed three tasks in order to separate the three stages explicitly. Consequently, all twelve pairs completed the co-creation task, and the differences between two experiment's final scores were significant. This indicates that the order of establishment would lead to form an effective symbol communication system. We suggest that the order has an effect of scaffolding the formation. Finally, we will discuss whether the order has an effect of starting small (Elman, 1993) for the learning at the different levels.