This is a great video by Zak George which demonstrates how to work with a new puppy, stopping biting, introducing a crate, using a drag lead, etc., all using positive training methods. There is a spot of advertising by his sponsor, but it does not detract from this really helpful video. Obviously, the dog is not a Cairn and we recommend only using a lead attached to a secure harness, not a lead attached to a collar, but everything he demonstrates applies perfectly to a Rescued Cairn.
Training a puppy can be fun!
Col. Potter Cairn Rescue Network