I find it easier to maintain a hard no-snacking policy, than to try to reduce snacking but with case-by-case exceptions. Stick to eating at mealtimes only, rather than allowing yourself to rationalise that slice of cake (it’s a colleague’s birthday, rude not to), bag of chips (I only had a small lunch) or dozen donuts (they’ll go stale if I don’t eat them, that’s wasteful).
Weigh yourself consistently (i.e. same time, same outfit) - I find it easiest to do straight after jumping out of the shower in the morning, post-poop and pre-breakfast, but ymmv. And the important part, record it. I have smart scales, which makes life easier, but absolutely not essential. There’s something very motivating about watching the line go down - and will quickly highlight if you’re on the right track, or if you need to cut back a little more.