To master mathematics at a graduate level, it's essential to engage actively with the material rather than relying solely on websites or videos. Textbooks are crucial for structured learning, and working through problem sets is necessary for understanding. It's recommended to ask questions about challenging problems to gain deeper insights. For those starting below high school level, foundational topics like trigonometry, calculus, and algebra should be prioritized. If already comfortable with high school math, pursuing a university-level program is advisable, covering subjects such as linear algebra, calculus, and real analysis. Resources like MIT OpenCourseWare, Khan Academy, and specific websites like Gerard 't Hooft's site and John Baez's blog can supplement learning, but they should not replace hands-on practice. Websites like learnerds.com can also provide valuable practice and community support for solving math and physics problems.