Today, after doing my grocery shopping, I decided I would make a simple (and somewhat obvious) post about shopping, and I can guarantee that these tips will help you save money shopping!
Firstly, whenever I go to the shops, I go for a reason. Many people I know have fallen victim to the shopping culture, where they spend half a day at the shops as a past time. This encourages needless spending. What began as a "browsing" trip, soon turns into buying yourself something you didn't need, going out for lunch, etc. If you want to save money, avoid going to the shops unless it is necessary. When you need something, you will know you need to make a trip to the shops. You will be surprised what you can go without when you don't think about it.
Secondly, spend wisely. Why buy a special packet of something (for example, a packet of lettuce leaves) when you pay more than you would if you just bought a head of lettuce? You pay less, and you will get more. This can be applied to a number of products. Sandwich ham is a great example of this. Many people refuse to eat any ham that hasn't been bought from the deli section. One of my friends has worked in the deli section of the local super market, and he tells me that the ham that is sliced in the deli is the same as the chunk of ham you can buy unsliced, with the only difference being the price.
Hopefully this was helpful. I apply these ideas constantly and it definitely works.