1. Uninstall any unnecessary applications by using an application like App Cleaner or CleanMyMac.
2. Clean up disk space by deleting duplicate files, unwanted downloads, and other temporary files with a disk cleanup utility like CCleaner.
3. Disable system restore points if you have Windows.
4. Move large files to an external hard drive or cloud storage.
5. Defragment your hard drive. This will help to increase the efficiency of data transfer.
6. Check startup programs to see if any programs are automatically starting which can cause your computer to slow down.
7. Remove malware and viruses if necessary.
8. Consider partitioning your hard drive. This will help keep all of your important files organized on one drive and all unnecessary items on another.