On OPIN you have the possibility to create:
1. Click on next to your username in the upper right corner and select the name of your organisation in the drop down menu.
2. Select the tab Projects in the menu on the left hand side.
3. Select a project and click on edit.
4.Click on the basic settings tab. At the bottom of the form you will find the options to select private or public projects.
5.Select whether your project should be accessible to all registered users on OPIN (public) or only for invited users (private).