I wouldn’t dare defile Douglas Adam’s memory by not mentioning that you should keep a towel with you at all times, but my second contender is a surprisingly short three-parter:
- never lie.
- never tell the whole truth.
- never pass up a chance to use a real bathroom.
This is a metaphor for life in general. If you find that all your interactions are negative, check yourself. Are you the problem in your relationships and interactions? How can you fix that? Clean your shoes.