I read the first half of "The School of Christian Perfection" with a group of ladies during Lent. Although I meant to continue reading a chapter a week, it obviously took me longer than that.
I was once a candidate for an order of teaching Sisters who follow the spirituality of St Alphonsus de Liguori and they had a virtue of the month set for each year. With that in mind, I noted that this book is 12 chapters long, which lends itself beautifully for meditating on one chapter each month. I will likely re-visit this book in that manner.