Starting from this point, all of the future publishing work will take place on the iTunes Connect website. As you already have a profile for your game from Chapter 7, Monetizing Your Game, you will be able to add some social stuff such as the Leaderboard and Achievements. Now you need to access this game profile again.

In the first part called App Video Preview and Screenshots, you can add five screenshots alongside a video for each targeted device. As you can see, Apple defines these sections by screen size, not by the device generation name. Make sure to upload the screenshots with their correct dimensions to avoid any further problems.

All of the other sections are about filling in your information, website, support e-mail, game description, the game category, the game rating, and choose to enable or disable some features such as Game Center. You need to write these things carefully as it will be the interface of your game on the App Store. Keep in mind that you can come here later and make any changes you want. Also, don't forget that any icon will be rejected if it is less than 1024*1024 pixels.

Now, on the top-right corner of the App dashboard page, the Save button will be highlighted, as you have already made some changes. It is a good idea to save right now. However, as you can see, the Submit for Review button is still grayed out, which means that there is something missing that has made the app ineligible for submission.

After saving, you'll find that the new icon has been added next to the app title, and also that there is some text indicating the current status of the app, which is currently Prepare for Submission.