I'm not going to make a list, but I've done many of the things already mentioned. I definitely shop more carefully and try to buy good quality items at a discount. I have disciplined myself to separate wants from needs. For example, I no longer need to delegate cleaning my home.
One of the most important things I do is to budget. Right now I am considering getting custom slipcovers made for my living room furniture, but the budget says "no". Never mind, I can look forward to buying them in the future (perhaps after the car is paid for).
Another is to reduce the temptation to spend frivolously. So I avoid malls and junk mail, both paper and electronic. I also try to use frequent flyer points and loyalty points to my advantage. For example, last year I had a free Caribbean cruise and a long distance flight. Just recently I got a superb new set of cookware for free.
As I live miles from most family members, there is little reason to buy souvenirs on trips. You know, the item you buy abroad because it would be a perfect gift for someone, and you buy another one for yourself because it's a bargain, and the bus is leaving so you have to make your mind up, and when you get home, you realize how hideous it is? Well, I'm done with that kind of impulse buying. I can now explore an interesting market and come out with nothing but a photograph. Ten years ago I would have bought jewelry, but I have enough.