Train
Trainline is a great website to coordinate a train ride to Newquay from London. You may be able to get one direct but many have one stop. Please try to board your train around 15 minutes before the ticket time. If coming directly from your flight in, you will need to purchase a train ticket for The Heathrow Express and ride that train (about 30 minutes) to Paddington Station for your main train. Generally that train is on Platform 2. Trainline can also be used from whatever destination you are coming from.