1. Choose someone to be Alice and someone to be Bob. If there are three of you, the other person will be Eve.
2. Bob should choose n and e, and read them to Alice.
3. Alice should encrypt a message with the n and e provided. Read this to Bob.
4. Bob should decrypt the message, using his phi and d values.
5. Eve should try to work out what the message was, using only the numbers overheard.