One of the easiest ways to save money and use less is to try cutting things in half. You will be surprised at how much you overuse when you start this process. One of my favorite books, The Tightwad Gazette, mentions this idea and I’ve been using it ever since I read about it.
Take whatever you are about to use and cut it in half. My first attempt was with dryer sheets. I started tearing the dryer sheets and using only half a sheet per load. I found that there is no difference in the result compared to a whole sheet. That was easy so I tried it with laundry detergent. Again, success! Next, shampoo, toothpaste and other personal items worked well. Automatic dishwasher detergent did not work with less. I still fill the cup, but I did find the store brand works just as well as the pricier stuff. Sugar in my coffee and butter on my toast worked well by using half and are probably better for my health too.
On the subject of food, look at the serving sizes. Start measuring out the serving sizes and you will be surprised at how much you over use. Creamer in the coffee is one that shocked me. I measured out a tablespoon and it is much less than the amount I was using. I tried using less coffee but I have to draw the line there.
Use your judgement, of course. Do NOT try this with prescription medicine, but do this with mundane things and see what happens.