Several different sources pointed me to a marvellous book on writing, Anne Lamott‘s Bird by Bird: Some Instructions on Writing and Life, published in 1994.
The title comes from advice her father gave to her (then) 10-year-old brother, who was struggling to start and finish a school project on birds:
“…he was at the kitchen table close to tears, surrounded by binder paper and pencils and unopened books on birds, immobilized by the hugeness of the task ahead. Then my father sat down beside him, put his arm around my brother’s shoulder, and said, ‘Bird by bird, buddy. Just take it bird by bird.’”
As usually happens with an enjoyable book, I burned through it in no time, and agree with the sources who pointed me to it that Lamott is laugh-out-loud funny. If you’re a writer, you’ll also laugh/cry/sympathize at the descriptions of painfully getting words to paper.