Use of bookmarks in form recordsetclone

[TimTDP]

I have never used bookmarks!
I want to create a recordset clone on a form, loop though each record and verify data entry.
This is what I have:

Set rstForm = Me.RecordsetClone

With rstForm
    .MoveLast
    .MoveFirst
    
    Do Until .EOF
        If IsNull(Me.cboSalesAreaId) Or Me.cboSalesAreaId = "" Then
            MsgBox "Please enter the ""Sales Area"" for customer """ & rstForm!CustomerName & ".", vbExclamation, "No Sales Area"
            GoTo Exit_cmdClose_Click
        End If
        
        If IsNull(Me.cboDriverId) Or Me.cboDriverId = "" Then
            MsgBox "Please enter the ""Driver"" for customer """ & rstForm!CustomerName & ".", vbExclamation, "No Driver"
            GoTo Exit_cmdClose_Click
        End If
                     
        .MoveNext
    Loop
End With

How do I use bookmarks to ensure that each record is reported?

Many thanks in advance