If you are using TurboTax Download/CD then there won't be a "take me back to my return" button. Just open the return and select the tab on top you like to work on.
If you using TurboTax Online, but you are on the Tax Home screen then follow the steps below to open your return back up.
- In TurboTax Online, sign into your account.
- Select Tax Home in the left menu.
- Scroll down to Your tax returns & documents.
- Select 2018, and then select Add a State (you're not actually adding a state, this opens the return back up)
- Select the area on the left where you need to make changes (My Info, Federal, State).