If you’ve never read George Orwell’s 1946 essay “Politics and the English Language,” treat yourself.
Written more than half a century ago, it remains as timely in 2014 as it was when he wrote it.
Unfortunately, in this essay Orwell discusses the political use of language to manipulate and obscure:

Orwell drew on Communist rhetoric for many of his illustrations, but our own times have generated the political euphemism ethnic cleansing to cloak the heinous reality of dislocation, rape, and murder.

However, every word of the essay will reward your reading, but the section that I keep going back to is the one in which Orwell formulates six rules for clean, honest writing:

1) Never use a metaphor, simile, or other figure of speech which you are used to seeing in print.
Observing this rule will not only eliminate cliché in your writing, it will preserve you from disseminating the pre-digested thoughts of others.

2) Never use a long word where a short one will do.
Many Latinate words in a row have the effect of softening and obscuring meaning. Be especially careful with strings of nouns ending in -tion.

3) If it is possible to cut a word out, always cut it out.
We can all benefit by going back over our work looking for such unnecessary words as just, almost, apparently, and a great many other superfluous adverbs.

4) Never use the passive where you can use the active.
Not only does the passive voice have the effect of slowing down writing, it enables the political writer to avoid placing responsibility. Compare:
The Indians were forced from their homes.
The government of Georgia forced the Indians from their homes.

5) Never use a foreign phrase, a scientific word, or a jargon word if you can think of an everyday English equivalent.
For all that we should be free to use the word “niggardly” if we wish, we can usually get our point across with the more familiar and less controversial stingy.

6) Break any of these rules sooner than say anything outright barbarous.
While we needn’t write billets doux for love letters, we’d be up a creek if we had to come up with “an everyday English equivalent” for such assimilated foreign expressions as laissez-faire, détente, and cliché.

TIP: Good writing is honest writing. Begin with a clear idea of what it is you want to say. Be prepared to write and rewrite until the words you’ve poured out on paper come as close as possible to the idea you wish to convey. Don’t use big words to impress, but don’t underestimate the intelligence of your reader.

And go back to Orwell from time to time.