Optimization starts with efficient data modeling, such as reducing table size and simplifying relationships. Query folding ensures complex transformations are pushed to the source system. Power BI development avoid excessive visuals per page and use optimized DAX formulas instead of calculated columns. Pre-aggregated data tables and efficient use of indexes improve performance. They employ performance analyzers to identify bottlenecks and refine visuals. Incremental refresh reduces processing time for large datasets. By following these methods, developers ensure reports load quickly and deliver a seamless user experience, even with high data volumes.