itch.io

Go to your store page.

1. Click Edit Theme
2. On the panel that opens on the left:
3. Select Grid from the dropdown box next to Layout.
4. Drag and drop your games into the order you want them.
5. Scroll down to the bottom of the list and click the Save button.

(My games are automatically sorted from oldest to newest - new games I add go to the top of the list.)