Say as little as possible to the officer. Do not attempt to convince the officer of your innocence. Do not be familiar or friendly in an effort to appear relaxed, normal, personable or to appear less guilty. Avoid offering any information at all. Don't even think. Just be quiet.
Never touch the police officer or make any motion that might be construed as an intention to touch him. When dealing with the police, keep your hands in view and don't make sudden movements. Avoid passing behind him. Also, never touch his equipment including vehicles, flashlights, pens or clipboards.