First you need to register yourself with your name, ID-number, email, and password, the last one of which can be registered after pre-registration and with using the temporary password sent in the auto-supply mail.

After the registration, from "Upload" link, fill up the data, select the file to upload and push "Upload" button.

You can check the status and replace the uploaded file if you have some corrections and before the submission deadline.

Here is an example of answers.