A home library is not a wall of spines. It is the eight or twelve books you keep reaching for, plus a little space for whatever comes next.
Buy for rereading, not for display. A novel you will lend to a friend, a history you still quote, a self-help title with one chapter you actually use — that is a library. The rest is storage.
A simple UK-friendly rule: one new book when you have finished two. Keep hardbacks for the titles you know, paperbacks for discovery, and leave a gap on the shelf so a new favourite has somewhere to go. If a book has sat unopened for a year, it is not part of the library. It is a reminder.
Start with the five categories we stock — fiction, crime, children's, biography, and self-help — and pick one from the list you already live. A small shelf, well chosen, will outlast a full wall bought in a weekend.