The Meditation for April is all-round good advice and completely straightforward, as well.
(For less-than-straightforward, but no less useful entries in this series, start here.)
This is from Book One, Number Ten
The Maxwell Stanisforth translation in full:
It was the critic Alexander who put me on my guard against unnecessary fault-finding. People should not be sharply corrected for bad grammar, provincialisms, or mispronunciations; it is better to suggest the proper expression by tactfully introducing it oneself in, say, one’s reply to a question or one’s acquiescence in their sentiments, or into a friendly discussion of the topic itself (not of the diction), or by some other suitable form of reminder.
This is always necessary advice to us pedants. No one likes an overly-fussy submissive. Or Dominant, for that matter. Be polite, basically.