For 11th and 12th commerce classes, focus on building a strong foundation in subjects like Accountancy, Business Studies, Economics, and Mathematics. Regular studying, practicing problems, and staying updated with the syllabus will help you excel. Stay organized, manage your time wisely, and seek help from teachers or peers if you face challenges. Engage in active learning, and consider exploring real-world applications of commerce concepts. If you have any specific questions or need guidance on a particular topic, feel free to ask!