George Orwell's six elementary rules

Never use a metaphor, simile or other figure of speech which you are used to seeing in print.

Never use a long word where a short one will do.

If it is possible to cut out a word, always cut it out.

Never use the passive where you can use the active.

Never use a foreign phrase, a scientific word or a jargon word if you can think of an everyday English equivalent.

Break any of these rules sooner than say anything outright barbarous.