When I walk into my public library, the newest titles are set on prominent shelves, so they are the first books visitors notice. You can do the same at home, so you'll remember to read your recent purchases.
Look through your books and move any new and unread titles together on one shelf so when you go looking for something to read, these options will catch your attention more easily.
Do you need more than one shelf for unread books? Is this a sign that it’s time to halt any new purchases? Do you need to schedule more time to read?