1. Always try to use the language so as to make quite clear what you mean and make sure yr. sentence couldn’t mean anything else.
2. Always prefer the plain direct word to the long, vague one. Don’t implement promises, but keep them.
3. Never use abstract nouns when concrete ones will do. If you mean “More people died” don’t say “Mortality rose.”
4. Don’t use adjectives which merely tell us how you want us to feel about the thing you are describing. I mean, instead of telling us a thing was “terrible,” describe it so that we’ll be terrified. Don’t say it was “delightful”; make us say “delightful” when we’ve read the description. You see, all those words (horrifying, wonderful, hideous, exquisite) are only like saying to your readers “Please will you do my job for me.”
5. Don’t use words too big for the subject. Don’t say “infinitely” when you mean “very”; otherwise you’ll have no word left when you want to talk about something really infinite.

- Letters to Children
Our Faith is not very likely to be shaken by any book on Hinduism. But if whenever we read an elementary book on Geology, Botany, Politics, or Astronomy, we found that its implications were Hindu, that would shake us. It is not the books written in direct defence of Materialism that make the modern man a materialist; it is the materialistic assumptions in all the other books. In the same way, it is not books on Christianity that will really trouble him. But he would be troubled if, whenever he wanted a cheap popular introduction to some science, the best work on the market was always by a Christian.

- God in the Dock
Returning to work on an interrupted story is not like returning to work on a scholarly article. Facts, however long the scholar has left them untouched in his notebook, will still prove the same conclusions; he has only to start the engine running again. But the story is an organism: it goes on surreptitiously growing or decaying while your back is turned. If it decays, the resumption of work is like trying to coax back to life an almost extinguished fire, or to recapture the confidence of a shy animal which you had only partially tamed at your last visit.

- English Literature in the Sixteenth Century