According to Kory Floyd in the Communication Matters textbook
Antecedent Phase
you haven’t joined yet, you’re thinking about the group in a general sense
Anticipatory Phase
you are about to join the group, thinking exactly what you expect from the group and its members
Encounter Phase
you meet the group, decide who will be the leader, reminding members of the expectations of behavior, setting official rules for conduct
Assimilation Phase
you start to accept the values, goals, and rules of the group. The group now has its own identity, and you are becoming an integral part of this group identity. Start enacting specific rituals and behaviours that signify you are part of it
Exit Phase
you and the other members exit the learning, work, and social groups, and the groups themselves may end