Back up any files you want to keep
Sign out of all accounts
Deauthorize apps and services tied to the PC
Create a bootable USB with a trusted OS installer or disk-wipe tool
Boot from the USB drive
Open the disk management or wipe utility
Delete all partitions on the target drive
Perform a full overwrite wipe if the drive is HDD
Use the drive’s secure erase or sanitize command if the drive is SSD
Verify the wipe completed successfully
Reinstall the operating system if needed
Remove the USB drive
Set up the PC as new or power it off