The calendar may still say summer, but retail giant Wal-Mart is encouraging consumers to get in the Christmas spirit now. With Labor Day more than a week away, the world's largest retailer is scheduled to launch its holiday season layaway plan four months before Dec. 25. Starting today, two weeks earlier than it did last season, Wal-Mart will allow customers to pay for nearly 40,000 items in installments. Shoppers will have 90 days to pay for their items. Merchandise will need to cost at least $10 and the total of items under layaway must reach $50, according to the company.