1. Type "system protection" at the Start screen and select Settings in the Search panel. You'll only see the one "Create a restore point" result.
2. Click or tap that result.
3. Enter a description for the restore point
4. Press the Create button. You'll then see a small info box titled System Protection with a progress bar and the text "Creating a restore point…"
5. The creation process tool less than a minute on my test laptop, a Lenovo T430 $773.10 at Lenovo. When it was done, the following satisfying message appeared:
And you're done. The next time your pal summons you to fix his misbehaving Windows computer, all you'll have to do is type System Restore in the Start menu (Windows 7) or Start screen (Windows 8), choose the restore point you created, and run through the wizard.