1. When you use a word, make it mean whatever you want it to mean. That way lies glory.
2. If examined carefully enough, every plot will turn out to be rubbish. If not examined carefully enough, any old rubbish plot will do. Do most people examine things carefully? I think, probably no.
3. Abhorrence of cliches is a silly fad of our time unknown in the great storytelling cultures.
4. Boxing things into narrow 'genres' is a silly fad of our time unknown in the great storytelling cultures.
5. All writing is really first person. When you write in third person, you are also creating the invisible narrator who is telling the story. Try not to make that person you all the time.
6. All writing is also second person. When you write in first person, you are also creating the second person who is listening to or reading the story in the world of that first person.
Try not to make that person me, because I don't like to read about love triangles with vampires and werewolves. Try not to make that person somebody who knows all the same stuff and thinks the same way as someone from your world, unless your world and the first person's world are the same world.
7. Don't have more than one differential equation per page on average, or more than three in a row on the same page.
8. In the next few centuries gender will become an optional extra for humans, so if you want your work to be appreciated by the far future, use only genderless characters.
9. 'A Viking never apologises and a Viking never explains.' (Hagar the Horrible) And the Viking sagas are still being read today. Coincidence? I think not.
10. 'Figuring out things for yourself is the only freedom anyone ever really has. Use that freedom.' (Jean Racszak, Starship Troopers)