once the chart is prepared and your e-ticket remains in WL after chart preparation, dont worry your ticket will be cancelled automatically and the refundable amount will automatically be refunded in your same account which was used for booking, you do not need to cancel your ticket manually, however you cannot travel on an waitlisted e-ticket after chart preparation, you will be considered as travelling without ticket and will be dealt as per railway rules.....alternatively you should look for another option for your travel