Once you have clicked on your desired products page, click on ‘Create your…” and you are then given two options. You can either upload an image directly from your Instagram account or from your device. To do this, simply click on either the ‘Upload from Instagram’ button, or the ‘Upload from my device’ button.
If photos uploaded are larger than the square format, the photos will need to be dragged into the desired position. This is done by clicking and holding onto the image and then dragging until you're happy with the images position within the format.