Immersive Virtual Reality (iVR) has gained popularity in education for its ability to engage students and enhance learning. With the growing use of avatars in collaborative iVR environments, there is a need for structured guidelines to optimize their effectiveness. This preliminary systematic literature review aims to synthesize key findings from relevant studies, investigates the potential of avatars in iVR education and proposes best practices to promote positive learning outcomes. Gathering data from various studies, the review provides initial insights that will aid future researchers and developers in effectively integrating iVR and avatars, optimizing them for the educational setting, and ensuring their effectiveness in enhancing learning outcomes.