Effective teachers must excel at communication. Even if you consider yourself a good communicator already, there is always room for improvement. Remember that communication is a multidirectional process. When you teach your first class, you may have students who interrupt, use undesirable behavior or disengage. Be patient and communicate your expectations early on.
You can also invite your fellow future teachers to form an interactive study group with you. Each person can take turns delivering a brief lecture, with the other group members assuming the role of the students. The feedback you gain from these mock classroom sessions can be invaluable.