One effective way is to minimize the number of visuals on a single page to reduce rendering time. Another approach is to use aggregated tables or summary tables to pre-calculate complex calculations and reduce query and processing time. Additionally, optimizing data models, such as removing unnecessary columns or tables, using relationships wisely, and defining appropriate data types, can also improve performance in Power BI. Finally, consider implementing query folding to push as much data processing as possible to the underlying data source.