As an administrator, you can create spaces using the end user UI or the admin console. In the admin console, you can also arrange the space hierarchy.
Admin Console: Spaces > Management > Summary
You can view and arrange the list of spaces in the admin console. The space Summary page lists spaces in the full hierarchy and provides a way to create spaces or edit their settings.
On the space Summary page, on the Browse tab, you can drag spaces up and down to reorder the list. Although you can't change where a space is in the hierarchy by dragging it, you can change that with the Move button, as described below.