Parameter to generate a log file to a script.

I am using below script. My script is not giving me consistent result.

May i ask, if I can use any statement with a script to get the log file generated so we could find out if my script is extracting exact user count or if it is failing i could get in log file which I could export via email every time it runs.

Any suggestions please? I am a rookie in writing power shell code so please tell me in detail. Thank you

Script I am using.

Import-Module ActiveDirectory

Get-ADUser -Filter { memberOf -RecursiveMatch "CN=status,OU=Test,OU=Users,DC=QA,DC=GU,DC=com" } -SearchBase "OU=Test,OU=Users,DC=QA,DC=GU,DC=com" -Properties cn, samaccountname, givenName, middlename, sn, mail | Foreach-Object {
    $group = ""
    Get-ADPrincipalGroupMembership $_.SamAccountName | Foreach-Object {
        if (($_.Name -eq "staff") -or ($_.Name -eq "student") -or ($_.Name -eq "faculty"))
        {
            $group += $_.Name + ","
        }
    }
    if ($group -eq "")
    {
        $group = "other"
    }
    else
    {
        $group = $group.Substring(0, $group.Length - 1)
    }    
    New-Object -TypeName PSObject -Property @{
        System_Role = "NONE"
    External_Person_Key = $_.cn
    User_ID = $_.samAccountName
    Passwd = "test1"
    FirstName = $_.givenName
    MiddleName = $_.middleName
    LastName = $_.sn
    Email = $_.mail
        Institution_Role = $group
    } | Select-Object System_Role, External_Person_Key, User_ID, Passwd, FirstName , MiddleName, LastName, Email, Role          
} | convertto-csv -Delimiter '|'-notype |% {$_ -replace '"', ""} | out-file c:\BB.dat -Force -Encoding ascii


** Here is need to add statement to get log file***

TechNet