You don't have to send the initial 1040 prior to filing the amendment.
You have to sign and mail the 1040X amended taxes along with any new tax document you received(like W2 or 1099)
See the link below on where to mail your amendment:
With my original w2 I filed with i was getting a return for X amount(hundreds of dollars) but with the amended i now ow 61 dollars to the IRS. Do i need to also send in the amount from the original return with the 61 dollars?
Have you received your refund from the initial filing already?
If you already filed and the return was accepted by IRS, you have to wait until you receive your refund before you can amend your taxes. You will add the refund already received in your 1040X and TurboTax will calculate the total amount you have to send to IRS(which will be the refund received plus the amount you owe).