The following describes how to leverage the $ENV:PATH syntax within powershell to add a value to the Path environment variable, please note changing the environment variables using this method only works for the current powershell session. If you wish to make this change persist in the registry then use System properties->Advanced->Environment Variables->Path->Edit->Edit Text
Example of appending directory “;c:\DRing” to the Path using $ENV:PATH
$ENV:PATH = $ENV:PATH + “;c:\DRing”
Validate the change by simply using $ENV:PATH
Display the environment variables using Get-ChildItem Env:
Note: if you discover that after updating the environment variables via system properties and they do not appear to propagate in powershell then log off and on and the changes should now appear after creating a new explorer.exe session. Alternatively try launching powershell from start menu as opposed to taskbar shortcut.