To delete temporary files in Windows 10, follow these steps: 1) Open the Start menu and type "Disk Cleanup" into the search bar. 2) Click on "Disk Cleanup" when it appears in the search results. 3) In the Disk Cleanup window, select the drive you want to clean up (usually your C: drive). 4) Click the "Clean up system files" button. 5) In the new window that appears, scroll down and check the box next to "Temporary files." 6) Click the "OK" button to begin the cleanup process. This will delete all temporary files from your selected drive, freeing up space on your hard drive.