Under Settings, click the Notifications header. You'll see a Add Notification button visible in the righthand side of the page:
After clicking Add Notification, use the various dropdowns to confirm settings like type of notification and frequency:
Low Inventory = SKUs which have low DOH (Days On Hand) [calculated on a rolling 30 day average of sales volume and flagging all SKUs with <14 DOH]
Network Summary = overview of fulfillment statistics
Click Create to complete setup of your notification.
Note: Notifications will be emailed at 5pm EST on the day(s) you've selected.