Part of living economically is not only the avoidance of unnecessary purchases, but also making things last; by "things" I mean anything you would use long-term - clothes, shoes, appliances - as well as your non-perishable grocery store items, such as toilet paper, shampoo, toothpaste, soap, cleaning products, etc.
With clothes it's really straightforward. We have work/play clothes, which we tend to treat a little more carelessly (and more often than not, we either got them for free or for a bargain), and we have good clothes, such as for Shabbat. Clothes go into the wash because they need a wash, not because they had been worn once. Of course, with children's clothes, being worn once usually means a wash is in order!..
Doing less loads of laundry means reducing your expenses of electricity, water, detergent, and wear and tear on the clothes and on your washing machine. Line-drying minimizes wear and tear, too, not to mention saves electricity.
Good shoes receive regular treatment of shining, oiling and polishing, which makes them last longer. I have a black pair for summer and a black pair for winter, and they are in such condition that I hope they might last years. Of course, for walking, yard jobs and home, I also have sneakers, mud boots, and slippers.
When it comes to non-perishables, I guess disposables should be mentioned. I wish I could say I don't use disposables, but I will be honest. I do. Just last night, we had friends over and I used paper cups because it was late at night and I couldn't face waking up to a sink full of dirty glasses. Sometimes, when you go out for a picnic, for example, using disposables makes sense. But generally I try to minimize that.
As for other non-perishables, I don't mean to imply gross things such as that you shouldn't wash your hair, skip washing your hands, etc. Use what you need - but not more than you need, like the manufacturers of every product would have you do (so that you run out soon and go and have to buy more). Have you noticed the enormous holes they make in toothpaste tubes? If I'm not careful and squeeze just a little bit too hard, half the toothpaste comes out at once.
I used to wash my hair three times a week, and thought I needed it. But then, one winter it was cold and I only washed two times a week, and I noticed that very soon, my scalp adjusted its oil production so that I had the same result as when I washed three times a week. Now I wash once a week, and find it more than enough to keep my hair in good condition. This, obviously, means I use three times less shampoo and conditioner.
It's important to keep your hands clean, especially when working in the kitchen, but you don't have to use soap every time. Using too much soap makes your skin dry. When I use detergents - such as for laundry, for floors, for windows, etc - I always use less than is recommended, and the results are very satisfactory. Remember, the instructions on the package are made by people who want you to use it all up and go buy more!