Morgan, first you have to enable custom sorting. Go to the top of the page and click on your shop name. On the left, look under "Shop Settings" and click on "Options". Under "Rearrange Your Shop," click on "Enabled." Go down to the bottom of the page and click the blue "Save" button.
Now, go back to your shop's page by going back up to the top of the page and clicking on your shop name again. Next to "Currently for Sale," click the blue link that says, "Rearrange your shop." You can sort and move things from there. :)
I group roughly by style and have been putting seasonal stuff on the first page. Right now, my front page is full of hearts. I'm not sure what I'll do next, maybe put some of my simpler items on the first page, perhaps all the pieces suitable for layering. Seeing your first page as your store window is a good idea, and we all know that stores change their window displays on a regular basis.