When you love a project it is added to your loves list and a message is sent to the project's owners. Loves are a great way to keep track of promising projects and show your admiration for the work of other community members. You can love a project from the following places:
On a project's profile page there is a Love button just below the Message Team button.
Main Projects Page
From the main projects page, you can click on the Love icon found on project previews.
In the home updates feed, you can love featured projects.