Using PowerShell credentials without being prompted for a password

I'd like to restart a remote computer that belongs to a domain. I have an administrator account but I don't know how to use it from powershell.

I know that there is a Restart-Computer cmdlet and that I can pass credential but if my domain is for instance mydomain, my username is myuser and my password is mypassword what's the right syntax to use it?

I need to schedule the reboot so I don't have to type the password.

The problem with Get-Credential is that it will always prompt for a password. There is a way around this however but it involves storing the password as a secure string on the filesystem.

The following article explains how this works:

Using PSCredentials without a prompt

In summary, you create a file to store your password (as an encrypted string). The following line will prompt for a password then store it in c:\mysecurestring.txt as an encrypted string. You only need to do this once:

read-host -assecurestring | convertfrom-securestring | out-file C:\mysecurestring.txt

Wherever you see a -Credential argument on a PowerShell command then it means you can pass a PSCredential. So in your case:

$username = "domain01\admin01"
$password = Get-Content 'C:\mysecurestring.txt' | ConvertTo-SecureString
$cred = new-object -typename System.Management.Automation.PSCredential `
         -argumentlist $username, $password

$serverNameOrIp = "192.168.1.1"
Restart-Computer -ComputerName $serverNameOrIp `
                 -Authentication default `
                 -Credential $cred
                 <any other parameters relevant to you>

You may need a different -Authentication switch value because I don't know your environment.