Teachers often repeat language learning tasks and materials with students year after year. Although some tasks do not render satisfactory outcomes, students' performances can serve as valuable historical autoethnographic data that teachers can reflect on to improve their teaching materials and language learning tasks. In this article, using autoethnography as a pedagogical tool, I share my thinking and experiences regarding one task type (the simile task), which I have used with students over the years to develop creative language use (language creativity). I reflect on various similes produced and attempt to discover how to redesign the somewhat imperfect task to optimize creative language use. In particular, I try to find new constraints that can be set up to funnel the creative behaviour of the teacher and students. Before promoting students' creativity, teachers must nurture their creativity under various self-imposed constraints. Teachers' personal experience is a valuable source when implementing creative language teaching. This article shows two task constraints that can be set up to stimulate creativity in language learning tasks: exclusionary constraints (avoiding confirmation-based salient patterns) and focusing constraints (requiring the use of violation-based salient patterns). It also shows how we can identify micro-constraints to be excluded or focused on.