Assuming you would like tips on how to make the Citra emulator run faster:
1. Use an SD card - This will help reduce game loading times and also improve overall performance.
2. Overclock your CPU - This can be done by changing the settings in your BIOS. If you're not familiar with this process, there are plenty of guides online that can walk you through it. Just be sure to research your specific CPU model to find out what its safe overclocking limits are.
3. Use a high-performance gaming PC - Ideally, you want a PC that has a fast processor and plenty of RAM. Both of these things will help Citra run more smoothly.
4. Close any unnecessary programs - When you're running Citra, make sure to close any other programs that might be running in the background. Having too many programs open at once can slow down your computer's performance overall.
5. Keep your graphics drivers up to date - Out-of-date graphics drivers can cause all sorts of issues, including slowdown problems with games like Citra MMJ