1) Click the "Remix" button and rename the project, include your first name in the new name. If you don't see "Remix," click on "Sign in" and then log in with your Scratch username and password. 2) Follow the instructions on the competition page to modify the project.
After you finish modifying your project: 1) Ensure your project name is descriptive and includes your first name, then save it as a .sb3 file on your computer. 2) Return to the competition page, upload, and submit your .sb3 project file.