When you next go shopping, don't buy one off pieces that don't go with anything else, instead think about what you already own and work out how the new garment will create more versatility and diversity in your wardrobe. If it doesn't create at least 3 new outfits, put it back, the likelihood is you'll either a) never wear it or b) have to buy something else to match it with. Either way it's costing you more money than the original item.