You should wait until the Internal Revenue Service (IRS) requests the Form W-2, schedules or forms.
The request will be made in writing within ten weeks from the date you mailed the return and the notice acts as a transmittal that enables the service center to match the W-2 you send with the tax return.
Do not send the Form W-2 separately before you receive the notice nor should you submit another return with Forms W-2 attached unless there is a change in your return that you are amending.