DON'T USE BIG WORDS
 ANONYMOUS

In promulgating your esoteric cogitations, or articulating your superficial 
sentimentalities and amicable, philosophical or psychological observations, 
beware of platitudinous ponderosity. Let your conversational communications 
possess a clarified conciseness, a compact comprehensibleness, coalescent 
consistency, and a concatenated cogency. Eschew all conglomerations of 
flatulent garrulity, jejune babblement and asinine affectations. Let your 
extemporaneous descantings and unpremeditated expatiations have intelligibility 
and veracious vivacity, without rhodomontade or thrasonical bombast. Sedulously 
avoid all polysyllabic profundity, pompous prolixity, psittaceous vacuity, 
ventriloquial verbosity, and vaniloquent vapidity. Shun double-entendres, 
prurient jocosity, and pestiferous profanity, obscurant or apparent.

In other words, talk plainly, briefly, naturally, sensibly, truthfully, purely. 
Keep from "slang"; don't put on airs; say what you mean; mean what you say. 
And don't use big words!

https://archive.org/details/humoroushitshowt00klei

Humorous hits and how to hold an audience; a collection of short selections, 
stories, and sketches for all occasions by Kleiser, Grenville, 1868-1953