Don’t conduct private correspondence on a postal card. Many persons consider this an insult. A purely business message may be thus sent, but even then the slight saving in postage is small recompense for the delay so often attending the delivery of postal cards.
Don’t use a postscript; it is unnecessary, old-fashioned, schoolgirlish, and in a particular, punctilious letter the omission of any important matter necessitates the rewriting of the entire letter rather than the use of a postscript. In very friendly letters one may be permitted to add the forgotten paragraph in the form of a postscript, omitting, however, the obsolete abbreviation, “P. S.”
Don’t write on a half-sheet of paper unless the nature of the correspondence permits the use of the ordinary business letter-head. If the note is short, write only on one side of the paper, but don’t tear a sheet in half for economy’s sake. The rough, torn edges, denote haste, ill-breeding, or carelessness on the part of the writer.
Don’t use tablet paper for ceremonious letters.
Don’t write on both sides of the paper to any but very intimate friends or relatives, they being disposed to tolerate slight departures from formality on our part.
Don’t meddle with foreign nouns or verbs unless conversant with the language itself; incorrect and ungrammatical usage is too apt to be the unhappy result. Even foreign names and titles should not be used without the exactest care as to their orthography and application.
This rule should be especially remembered with reference to all matters destined to pass through hands editorial.
Don’t erase misspelled words in letters of any moment. Recopy the entire missive.
Don’t quote too constantly.
Don’t underscore your words, unless they express something very important.