If you want to prepare another return using TurboTax Online, you will need to set up another account. TurboTax is set up to be one tax return per account.
If you're preparing multiple returns for family members, it's more economical to switch to the TurboTax CD/Download software, which lets you e-file up to 5 federal returns at no additional cost. More info
Below are instructions on how to prepare another return
Thanks for asking! Never start another return by going back and overwriting everything in the return you just filed. This will replace your info, which means you won't be able to retrieve your return later.
Follow this procedure instead:
Instructions