It is explained in that section, but there's kind of a lot of info so maybe it doesn't stand out as well as it could. :/
And though Alex explains it well above, perhaps adding an image would be helpful. Eh, I'll just basically repost this bit again along with the image:
To restart the game, you'll first need to click on the main
MENU, which is the little white star symbol in the upper-right corner of the screen. Then click the
up arrow symbol to get to the
LOAD screen shown below. You'll see that the screen has several circles (save spots). Now click on the first circle (numbered '0') showing the observatory house of the space gnome, and then click the check mark to confirm and you'll be good to go.