Treasure Phillips, right, of Groton, teaches Heather Christie, of New London, how to staple and organize coupons during her advanced couponing class at the Public Library of New London on Saturday. Christie attended the class because she fosters dogs and cats for Stray from the Heart, a nonprofit animal rescue organization, and wants to learn how to save money when purchasing dog and cat food. During the class, which focused on efficiently cutting and organizing coupons, Phillips emphasized her motto, "buy what you need when you don't need it." Phillips recommends stockpiling common foods that have extended expiration dates when they are on sale or you have coupons. For example, cranberry sauce is commonly on sale during the holiday season. Planning ahead, making grocery lists to avoid impulse buys, and combining store sales with the use of coupons has allowed Phillips to save an average of 80 percent to 90 percent when grocery shopping. If her family does not need the food, then she gives it to others. Phillips donates food to the local food bank at least once a week, because of her tremendous savings and a passion for shopping.