I've been brought up to be quite frugal, so it's something that's natural to me.
For example:
- I spend the least on shoes/clothes and usually wear them even when they start to develop holes.
- I do the same for day to day things like food/cleaning stuff etc, I usually always get the cheapest stuff or buy in bulk.
- I don't really buy socks and underwear, I usually wait until Christmas when I get them as presents
- I much rather repair things myself rather than spend money getting it done by someone else/to buy replacements. The most ambitious example was making a replacement PSU for a C64 by getting a 9v AC and 5v DC adapter I had laying around the house, soldering them to a DIN socket. It looked rather janky as it meant plugging in two adapters, but it all worked fine without causing a fire.