Lucian of Samosata Rhetorum praeceptor 16

[16] “That is what you must contribute yourself. The rest you may now see and hear by the way, as you go forward. And next I shall tell you the rules that you must follow in order that Rhetoric may recognize and welcome you, and not turn you her back and bid you go to, as if you were an outsider prying into her privacies. First of all, you must pay especial attention to outward appearance, and to the graceful set of your cloak. Then cull from some source or other fifteen, or anyhow not more than twenty, Attic words, drill yourself carefully in them, and have them ready at the tip of your tongue —‘sundry,’ ‘eftsoons,’ ‘prithee,’ ‘in some wise,’ ‘fair sir, and the like. ¹ Whenever you speak, sprinkle in some of them as a relish. Never mind if the rest is inconsistent with them, unrelated, and discordant. Only let your purple stripe be handsome and bright, even if your cloak is but a blanket of the thickest sort.