When I began seriously frugalizing my life a year ago, I started with the big wins. Seeing the needle move quickly is encouraging and motivated me to continue. If I'd started with difficult, somewhat fussy moves, like frugalizing my soap budget, there's a good chance I would have given up.
It's somewhat personality dependent, but I think it's dangerous to take too incremental and gentle of an approach. If I want to change my life, I want my life to change, dammit! I won't be happy with small milquetoast changes like buying used clothes instead of new ones, or hunting for sales.
I prefer to take things in passes. The idea is to make a bunch of rookie mistakes as quickly as possible. Some people try to avoid ever making rookie mistakes because it's embarrassing. To me, it's far more embarrassing to be five years in to some endeavor and have little to show for it, because I never allowed myself to fail even a little bit. It's very difficult to get something perfect on the first pass, and I don't try. I do my homework so I don't hurt myself or break (too much) stuff, but otherwise I just get on with it and keep my eyes open. ("Ah! *That's* why it's really important to overlap housewrap tape 3" on each side of the seam. Okay, easy enough to fix.")
The biggest three expenses for most people are housing, transportation, and food. If you can move the needle here, even a little bit, that's going to be a big deal. These are the first passes I took:
Housing. For reasons that seem vague to me now, I was living in an expensive rental a year ago. That was an easy fix: I negotiated a win-win early exit from the lease and returned to full-time Serenity living. $1,900/mo immediate savings. Not everyone can (or wants to) live in to a 68sf metal shoebox. Remember that this isn't an advice blog - I have no idea what you should do with your life, I'm just telling stories about my life.
Transportation. I didn't make any changes to my transportation setup, actually. I have a twenty-year old Toyota that I paid cash for and do work on myself, and I don't commute. Also, Covid hit, so I stopped going on trips. Still, my truck burns almost $100 a month just sitting there in insurance, tires, value depreciation, and maintenance costs. I have big plans for addressing that, but shh it's a secret.
Food. Reducing my food budget was the easiest. I stopped eating out (this was extra easy due to the Covid shutdowns) and drinking alcohol. That was an immediate 50% reduction, with the bonus that I ate healthier and probably strengthened my immune system.
By focusing my efforts on the low hanging fruit of my life, I cut my expenses by about 69% in three months.