One thing I do is write them down. For example, I have a kanban board (like trello) that I use to keep track of ideas. Whenever I feel like starting some random project instead of doing what I’m supposed to be doing, I put it on the board. That way, I’m not afraid that I’ll lose the idea, and I can come back to it later and see if I really want to make it a priority. For financial impulses, etc, I add the thing to a wishlist, so I’m not afraid I’ll forget about it, and I can come back and review. For simpler impulses, sometimes it’s good to recognize the need and (if it’s safe, healthy, and appropriate to do so) just take care of it quickly before you start overthinking it and accidentally wind up in hyperfocus.

In general, I think it’s a good idea to take stock of what the impulse is asking of you. Maybe you don’t really want to spend $200 on specialty cooking ingredients online; maybe you’re just hungry and could use a creative outlet. Above all, I find that I’m inclined to punish myself for impulses by making acquiescing to them more cumbersome. I have never found that strategy to be effective; it usually just makes me feel bad. That’s why I changed my approach. I find the methods above much more useful, and they don’t contribute to the harmful idea that my neurodivergence / disability, or any perceived lack of productivity it may cause, is some kind of moral failing.