Sales Order Automation - Shipment Dates

Sales Order Automation - Shipment Dates

Hi,

I am having trouble figuring out how to set up an automation.

Scenario - 
Customer issues a new order with a ship date 4 months out.
I enter a sales order with the appropriate "Expected Shipment Date".
I want ZOHO to notify me (either email or pop-up) to prepare the shipment for this order on the expected shipment date.
**CAVEAT** I don't want to get a notification for every single sales order. I only want to be notified of "future shipments".

I've created a few workflows rules, but none of them seem to trigger.

Any help would be greatly appreciated.

Thank you,
Manny C