Keep grains, spices, flour, sugar, etc., in a dry, cool and dark place, keep dairy products in a frige, never freeze products twice and store everything the right way, so that all your goods last longer.
Stay in a small town that is close to the one you actually want to visit. It often appears that the prices for living are so cheaper there, that you can save a lot of money by living there and driving/taking a bus to the turist town every day.
You can make your own cleaning products that will work as good as the ones you could buy in a store. In addition, they will cost you little and are healthier. Popsugar offers a lot of recipes for cleaning products.
If you are working in a big company, there is a high probability that you can have some perks and discounts such as gym membership, concerts, etc. Get to know them all, use the ones you need and save money.