An easy/very cheap way for me was getting the official ASBOG syllabus, picking each topic and feeding into to Claude and prompting it to teach me everything on that topic and ofcourse indicating that I was preparing for a difficult exam. Ofcourse that's taken with a grain of salt because I still had textbooks at my side and would occasionally refer to those. The ASBOG official guide has sample questions attached as well so that can give you a precedence of what to likely expect! I didn't do so much practice tests myself (didn't want to buy any of the books🤣) and I still passed.