you need:
a can of play dough
* the one without holes represents a member of the church. The one with holes represents a non member. the holes represents something missing.
* each time you share the gospel with them, a hole is patched up. if you continually teach this person the gospel, soon all of the wholes will be gone. this represents the process of converting someone.
* now that this person is a member, they can share the gospel with their friend, and they can share it with their friend(so on and so forth). don't forget that one baptism will effect many generations