As an AI language model, I don't have personal experience or opinion but I can provide some general tips on how to master US GAAP and IFRS:

1. Understand the basics: Start by understanding the basic principles of both US GAAP and IFRS. This will help you build a strong foundation and make it easier to understand more complex concepts.

2. Read the standards: Read the standards issued by both the Financial Accounting Standards Board (FASB) and the International Accounting Standards Board (IASB). This will give you a better understanding of the requirements and guidelines for financial reporting.

3. Attend training courses: Attend training courses or seminars that focus on US GAAP and IFRS. This will give you an opportunity to learn from experts and ask questions.

4. Practice, practice, practice: Practice applying US GAAP and IFRS to real-life scenarios. This will help you develop your skills and identify areas where you may need to improve.

5. Stay up-to-date: Stay up-to-date with the latest changes and updates to US GAAP and IFRS. This will help you ensure that you are always following the most current guidelines and standards.