When a new user signs up to Twine, they must tick a box called Terms and Conditions. By default, this contains Twine's terms of service.
You can edit this with your own terms by heading to Settings > Terms & Conditions. You can either edit an existing entry or create a completely new set by pressing Create draft.
Please note when creating a new draft it will be pre-populated with the previous version or the Twine default should this be the first draft.
Once your done making your changes in the text editor, scroll to the bottom and press Create Draft.
Now, your new version of T&Cs will appear in the list, like below.
Press the Publish to make them live. This will replace Twine's default terms and conditions and create a new version.
Now when new users register for Twine, they will have to accept these terms by ticking the box at the bottom of the form. They can view the T&Cs by pressing the 'Terms and conditions' link.
And they'll be taken to a page that looks like this:
When you make changes to these terms and conditions, existing users will need to reaccept these terms the next time they log in. They'll see a page like this:
They'll just need to accept the new terms, and away they go!