added user-friendly installation instructions

Author: admercs

README.md

@@ -66,7 +66,12 @@ documentation for the latest release is published on on learn.microsoft.com.
 ## Installation
 
 To install **PSScriptAnalyzer** from the PowerShell Gallery, see
-[Installing PSScriptAnalyzer](https://learn.microsoft.com/powershell/utility-modules/psscriptanalyzer/overview#installing-psscriptanalyzer).
+[Installing PSScriptAnalyzer](https://learn.microsoft.com/powershell/utility-modules/psscriptanalyzer/overview#installing-psscriptanalyzer) or simply open PowerShell in a Terminal and run:
+
+```powershell
+Set-PSRepository -Name PSGallery -InstallationPolicy Trusted
+Install-Module -Name PSScriptAnalyzer
+```
 
 To install **PSScriptAnalyzer** from source code: