I started doing this meditation a long time ago and I still use this technique in my waking and conscious life often to cope with anxiety, negative thoughts and going into any situation that makes me nervous. Once you've done it a few times you'll be able to follow the same steps and less than a minute to calm your nerves and feel open and positive towards the person or situation you're encountering. 

This one has an intro for a little more detail but if you want to skip straight to the mediation look for the one titled Meditation: Open your mind and heart_No intro