Since you e-filed you do not need to mail anything unless we tell you to. The goal of e-filing is to eliminate as much paperwork as possible. There are a handful of situations where you might have to mail something after e-filing, for example if your return contains Form 8453. You may also have vouchers, if you owe, such as the 1040-V to mail with your IRS payment.

We do recommend that you print your return for your records after your e-filed return has been accepted. https://ttlc.intuit.com/replies/3302289