Can you point out some reference books on literary criticism – from a theoretical as well as practical point of view – to hone and systematize my skills, acquired through first-hand reading of lots of books.
A very good read which is informative and entertaining is, How To Read Literature Like a Professor, by Thomas C. Foster.
Another very good book is Literary Criticism: An Introduction to Theory and Practice by Charles Bressler. A bit more academic, but quite good.
One of my go-tos is "Literary Theory: A Very Short Introduction" by Jonathan Culler. It's great for people who are new to literary theory, or for veterans that are looking to brush up on the basics.