Use your hand to indicate relative pitch while teaching The most important part of teaching rounds is to make sure that no one feels too rushed or left out.
Many people are very shy about singing, and nervous about their voices.
Be encouraging, try to find leaders who know the round and can help on each part to be a strong anchor for the others. Break up long rounds into smaller pieces, and sing those pieces over and over. Be sure to sing the pieces together, too, so people don't get lost when they try to remember which line comes next. Do similarly with the remaning lines. Never hesitate to go over rough spots, and try to encourage your singers to be willing to ask that one part be sung in isolation.