For just about as long as I can remember, I've wanted to live more simply. It didn't/doesn't matter how simple my life already is or was; I've always wanted to simplify it even more. More sleep, less stuff, more time, less stress, more space, less clutter. I used to want to be a nun. That being said, I'm a packrat and don't find severe aesthetic asceticism in a house.
Still, the simple life is attractive. Happily, simplifying and scrimpaliciousness in general have a lot of factors in common, so the one tends to feed nicely into the other.
It may not seem like a step toward simplifying your life, but the first best thing that anybody ought to do if they want to live more simply and/or more cheaply is to learn how to cook, and cook well.
Restaurant food, unless you're specifically going to a restaurant that serves explicitly healthy food, is not good for you. It's not meant to be eaten every day, or even every week. If you wouldn't eat fast food every week, check the nutrition facts at your favorite dinner spot and ask yourself whether you should really be eating that every week either. Mr. Scrimp has worked in restaurants for years, and you should hear what he has to say about the gallons of cream and pounds upon pounds of butter that restaurants put in everything. Everything.
One of the easiest and quickest ways to cut costs in your budget is to stop buying pre-prepared food and make your own. There is no aspect of this that isn't a good plan, believe me. Your food will be healthier, cheaper, and, once you've had some practice, just as delicious, though usually in a different way.
Mr. Scrimp and I are fortunately matched in that we both already loved to cook before we got married. Without ever having the energy or interest to put into being pretentious or really crazy about it, we're both foodies. So it's been fairly easy for us to not eat out in favor of cooking at home.
Even if all you know how to do right now is boil pasta and make sandwiches, start thinking about eating more pasta and sandwiches while you learn how to cook food that's good enough to be worth staying home for. Once you learn how to do it you may find you're surprised about how much people charge in restaurants for food ingredients that you know from experience are very cheap. It isn't that restaurants gouge their prices, necessarily, but if you go out, you pay not only for the food itself, but for the handful of prep and line cooks who got it ready, the chefs who cooked it, the hostess who seated you, the waiter who took your order, the server who carried it out, and the busser who cleaned it up.
I kid you not, because we're both willing and able to cook for ourselves and each other, Mr. Scrimp and I are eating this week (that's 7 days) on less than $40, which we spent exclusively at Whole Foods. Whole Foods is hardly a cheap grocery store, and before we started really scrutinizing what we spent, we could easily drop $70 a week there. None of what we bought was processed or pre-cooked or microwaveable. To tell the truth, we don't even own a microwave.
My point is, if you're willing to do a little extra work, you can spend much less money, spend more time with your significant other (if you have one), and eat better food.
All of the above not only applies to restaurant food but to convenience food--pre-cooked dinners, chips, ramen, whatever it is. Those things are cheaper, yes, but if you rely on them to eat frugally, you're on the way to destroying your health in the name of saving money, and the truth is, that's just not worth it.
It goes once again back to the gap between broke and poor. Poor is a mindset that gives up and takes the lowest common denominator without being ambitious for more. Poor lives on ramen. Merely broke says "well, I don't have much money, but I'm going to use what I've got to get not only the best value but the best quality."
I'm formulating an entry on a few of the most basic cookbooks that every adult ought to own. If you can read and have basic hand-eye coordination, you can cook from a cookbook.