For me, it's easier to go to the HTML version (when you create an account, it should give you the option to switch over. I don't know if you can after you've started doing stuff, but it's given me the option to switch to HTML before) because then you see a screen with an orange banner and below it you see "upload tools" and below that you see "manage files." In the manage files, you can just hit "+ new page," give it a title, and have a new page. Then you hit the pencil to edit (if you hover over it, it tells you what it does, like edit, rename, delete), either paste in your code or do up your own code, hit the save, and it takes you back to the main page. Then you can click on the title of the document (under the "file name" heading) and it shows up in a new window.