The most effective savings habits are the ones you do not have to think about. Automation beats willpower, because it works on the days you are tired, busy or distracted — which is most days.
Start with a waiting rule. For anything above a threshold you set yourself, give the purchase a day or two before committing. A surprising share of intended purchases quietly lose their appeal once the initial impulse fades, and the ones that survive tend to be worth keeping.
Audit recurring charges a couple of times a year. Subscriptions are designed to be forgettable, and forgotten ones are pure loss. Fifteen minutes with a bank statement usually pays better than an hour of bargain hunting.
Group your errands and your orders. Consolidating purchases reduces shipping costs, cuts down on impulse add-ons and makes it easier to compare what you are actually buying against what you planned to buy.
Finally, give your savings a destination. Money that is merely not spent tends to get absorbed. Money moved somewhere specific — a fund, a goal, a planned purchase — is far more likely to still be there next quarter.