To create a project click New project in the upper right corner of the dashboard and a new window appears. Then give your project a name and decide if the project is going to be visible to Project members only or to All team members.
The Project members only can be seen only by invited users and the All team members can be seen by everyone on the team, but only the invited users can edit it.
To invite people to the project, click the avatar icon and then the Manage users link. A window for managing users appears, where you can add as many users as you want and assign them different roles.