Step 1: Click on Stock and then select Maintenance.
Step 2: Select the item which you would like to setup sell date on.
Step 3: Click Edit to make the necessary changes on the selected item.
Step 4: Click on the General tab.
Step 5: Enter the number of days in the Shelf Life field.
Step 6: Click Save and close the select an item window.
Step 7: Follow the normal process of exporting to the tills, sign off/on for the changes to take effect.