Learn to apreciate cheap microwave meals, I go to iceland as there best value for money, £1 for 500g, most for that price only give about 400g. when you go to buy food, hunt around the area for good deals, like when I was in derby, I managed to find a shop that was doing Two 500ml bottles for £1, buy the pepsi max and that's 1.2l just be ready to hunt. If you have your own oven/hobs then the best thing is cook your own food, takes a while but it's the cheapest, my advice is google for recapies for inspiration.