If you are sending in your tax payment with a 1040-V, send it with your check in a separate envelope (without your tax return). Do not staple your check to the 1040-V. Be sure to write your name(s) and Social Security Number(s) on your check.
See also the TurboTax FAQ about the form 1040-V at:
https://ttlc.intuit.com/questions/1900609-what-is-irs-form-1040-v-payment-voucher
