In general avoiding situations when you only rely on your willpower gives much better results than fighting yourself. When I think I should loose weight I only buy boring ingredients that require preparation to be tempting in any way. If I get strong cravings I just eat some random vegetable and try to better plan mealtimes next day. It's much harder when living with uncooperative partner or parents that like always having snacks in their kitchen. We're literally built to eat food whenever it's available.