If you completed your return but did not file, and now need to get back into your return, you can do the following:
1. Sign into your Turbo Tax account
2. Click on tax home or take me to my return
3. Scroll down till you see Your tax returns and documents
4. Click on your 2018 return, and then select add a state (you are not actually adding a state, this just prompts the correct menu)
5. Navigate to where you need to on the return
When you have completed your return for the final time, go to the file tab and complete all the questions and file your returns.