The version history panel
Now that you have submitted your first prompt, you can see that a copy of the submission has been stored in the history list (see the area highlighted in red).
You can therefore update your prompt to test different versions and ideas. Remember: every time you submit a prompt, a copy is stored.
If you want, you can also easily restore an older version. Just click on the version you want to restore, and click on the bottom “Load in Editor”.