This book takes the form of a series of letters to an aspiring writer, who has produced one short story, which Bird kindly picks apart -- avoid cliched phrases, try taking out all the adjectives and adverbs, spend time choosing a title. There is advice on writing as a career, too: forget about the housework (tick), never use a word processor (well...)
Though Dear Writer was first published in 1988 and some of its advice has dated (hints about how to post a neatly typed manuscript, for example), I see that a newer version came out in 2013. I suspect that most of the original content was preserved, because the advice in here is very solid. Well worth a read.