One of the ways we can live the way we do is by not buying very much (which means not spending very much) - at least in the way of stuff or things.
I am going to start with how little we bought for our newest little one. The hospital we birthed her, gives every new baby a new car seat - every one - there is no income checking - just every baby gets one. I then used the previous carriers from our other babies, even our lovingly used Ergo.
This is the first baby that we have a wooden high chair - a $5.00 find at an antique shop that was going out of business. We found a sweet wooden table and chair set for $3.00 at a yard sale this past summer. If we can't find something within our budget, we just do without.
We have been blessed by sweet friends with some hand-me-downs and cloth diapers. I have only purchased two diaper covers from a small home business. They dry very quickly, have kept her clothes dry and right now we only have two. We could use another two, but we have been making do by washing the used one out under water and hanging it to dry.
We put the prefolds right in the cover. Some of them are close to being retired to the rag pile. I was blessed to find 12 in nearly new prefolds at a thrift shop a few weeks ago for only $3.00 for all 12.
I can get very distracted and yearn for new things for Emmy when I look through some beautiful toy catalogs like Nova Natural or see some beautiful handmade toys in Etsy shops, for example. But unless it is really, really necessary, or super special, or something that can become an heirloom, we don't buy new for the littlest in our home. We have a wooden play kitchen that we purchased 10 years ago and it has been used for each child since. Otherwise, toys consist of the ones we make, or find at yard sales and thrift shops. She is very happy with a child size broom in one hand a paintbrush in the other.
We use costume jewelry for distraction during church. She enjoys running her fingers over the beads and putting them on her wrists. (Of course, please be careful if there is any chance the beads could become loose and your child puts things in her mouth.)
I do have a weakness for books and do purchase new on occasion but find most our books used.
I do buy yarn to knit special pieces, of course. But then again, I do try to stay on the affordable side and have been gifted yarn as well as bartered for yarn.
As far as feeding, I have exclusively breast fed and am blessed to not have had to use a bottle at all. We don't buy baby food and instead mash up our food and then offer finger food as more and more teeth come in. We also don't buy sippy cups and instead teach little ones to use regular glass cups (usually the small canning ones that don't break easily). Emmy also uses a regular teaspoon or a wooden one our neighbor made for Abraham when he was born. But she uses a regular bowl and has not broken it yet:)
I think what helps the most in not spending on new things is to avoid browsing too much online or in all the catalogs that have started coming in the mail. We generally don't go to "big box" stores, plazas or malls to shop. I don't remember the last time I entered a Walmart or Home Depot, for example. I think it is so easy to buy things in those stores that you didn't intend to buy because "it is such a good deal" or "wouldn't it be nice to have one of these".
It is also helpful to practice contentment and when a new "want" creeps in, to really evaluate how it would or wouldn't change things, the cost of the item, if I can wait and look for it second hand, and finally, if purchasing that item would support another family or small business while respecting the environment.