Is this assuming they - the person you are about to teach - is a 'blank slate?" If that is the case, then I would teach them to:
1. Learn the difference between what they are and what they are not, i.e. to watch out for the false identification with the mind and emotions as themselves, rather than the mind being their most powerful tool.
2. I would encourage them to learn to read and then to read widely; all manner of subjects, for the they would be more creative and innovative.
3. I would teach them the value of keeping fit and healthy but without their becoming hooked on fitness at the expense of fun and enjoyment.
4. I would teach them that 'being in love' is a need and that if you look to another for your happiness you'll be risking your own automomy and happiness. Real love and being in love are not the same thing.
5. I would teach them to understand that all the good things in life are to be found inside rather than outside. Also, that the only constant in the universe is their own Awareness as witness to what is constantly changing.