We decided it was time to nix the dummy when DS1 was almost 3. He only used it for sleep, but he "had' to have one in his mouth and one in his hand when he was going to sleep. The crunch came when he started waking at night because he'd lost the one in his hand

Anyhoo ... we were going on holiday for 10 days so I seized my opportunity. On the drive to our holiday place I told DS1 I'd accidentally left his dummies at home. I made a big deal of "OH NO, I'm so sorry!!!". That gave me a few hours before bed time for him to get used to the idea he wouldn't have them for a few nights.

The first night he went to bed ok, he seemed to understand he wouldn't be getting his dummy(ies). And that first night he woke a couple of times and sobbed for his dummies. All we could do was comfort him and help him get back to sleep. We certainly didn't have a terrific night's sleep as he was pretty restless, but then again he was sleeping somewhere strange too.

After that he would say (on holiday) "no dummies mum, you left them at home". And he didn't wake up again looking for them. When we got home he was totally fine with not having his dummy.

Good luck - the "thinking" about how to do it, is probably worse than actually doing it.