Once redirected to the retailer's site to complete your order, you may see a Gift Message option to send directly with your gift from the store. 

If the store does not offer this option, after the purchase is complete, you can return to the MyRegistry Gift List to update the purchase. After the gift is updated, you will given the option to send a Gift Announcement Message. This will be sent via the registry and can even be scheduled for a date of your preference!