New-Self​Signed​Certificate
PS C:\tmp\Azure> New-SelfSignedCertificate -CertStoreLocation cert:\currentuser\my -Subject "CN=Local Code Signing" -KeyAlgorithm RSA -KeyLength 2048 -Provider "Microsoft Enhanced RSA and AES Cryptographic Provider" -KeyExportPolicy Exportable -KeyUsage DigitalSignature ` -Type CodeSigningCert
PSParentPath: Microsoft.PowerShell.Security\Certificate::CurrentUser\my
Thumbprint Subject
---------- -------
FBEA9166C4E1429775EB6BDEE47E54E49083811C CN=Local Code Signing
$cert = @(Get-ChildItem cert:\CurrentUser\My -CodeSigning)[0]
Set-AuthenticodeSignature .\your-script.ps1 $cert