I have a magento site set up and have altered the onepagecheckout file so that if the table rates shipping method is selected, it displays an extra couple of fields asking the customer to select a prefered delivery date and time. As a complete novice to modules, I am having difficulty getting these fields to update the database (haven't event got to trying to display them yet!) Don't get me wrong, I have found the odd tutorial out there - http://www.excellencemagentoblog.com/magento-add-custom-fields-checkout-page for instance - but I can't seem to get my head around it all. Is there a reasonably easy way to achieve this?
Cheers