When you share your project on Facebook, the project image or banner, the project title, and the project description text will be displayed. Below is an example of how it will appear. 

1. Image: It will take the project image, if not available, it will take the project banner. If either is not available, they will take a random image from the page

2. Title: It will take the project title

3. Text: It will take a random bit from the project description

Read the article Share and Promote your Project and Tools to understand more about the social media tools you can use to promote your project.