if you're doing it on your own, it helps to have a motivating story. there are a category of math book that is historically driven. you can pick a topic and typ

if you're doing it on your own, it helps to have a motivating story. there are a category of math book that is historically driven. you can pick a topic and typically find a really strong and well-written book on the history of that topic, or just pick up a book on the history of mathematics. these will give you solid examples that you can relate to, give you the motivating story of the persons who discovered the mathematics, and give you enough information to decide whether you want to explore that topic independently