Hi there, I have a nervous laugh, too, and I hate it. I have learned to deal with it at work, though, by developing what I call "Customer Service Mode", which helped me so much at work, I find myself using it in social situations now when I'm with unfamiliar people, or if my brain's too tired to deal with paying constant genuine attention to people, but I care about them and don't want them to think I'm rude or uninterested. I trigger it by putting on a big, genuine-looking smile, which I spend a bit of time studying in the mirror (close your eyes somewhere alone with a mirror, think of something that makes you happy, and then try smiling. when the smile feels 'real', think about which facial muscles you're using, once you've identified them, open your eyes and check your smile. adjust as needed until it's right and then practice!) I then slow my speech and become very polite, politeness helps, because all the meaningless extra words give you time to 'slow your brain down' and reduce anxiety. I never ask "How are you?" to someone I have just met, I prefer a warm-sounding "Good morning/afternoon" in professional or formal setting, or "Hello" (drawing the 'o' out a little makes it sound more friendly) when it's less formal. For some reason I can't say "Hi", it always comes out wrong and then I stress out about it, so I needed to find alternatives. I also speak using my throat more than usual because it makes my voice less harsh and more friendly and warm, while still maintaining some authority. Again, practice, practice! So anyway, I see a customer, take a deep breath, put on my smile and greet them "Good mooorniing". The added bonus is that it easily steers the conversation toward the weather, which is boring but easy.,As opposed to them actually telling you how they are, which is terrible because I don't know what to say, I get flustered, and say something inappropriate or rude and then stress about it the rest of the week (and random moments before bed for years to come). I also found someone at work who was really good with customers and studied her (listening only!) to pick up tricks. I still get overwhelmed in conversation or social settings, usually if I'm tired or hungry. So good sleep, and regular meals (muesli bars are great between meals if you can stand the texture of oats) are the building blocks. It won't happen overnight, but if you treat it as a new thing to teach yourself then it becomes routine to practice. I still practice when I'm alone. This worked in my situation, I don't know if it will in yours, but you may be able to integrate some of it into a version of your own?

This makes me sound like a robot, but if I don't do these things I either get so nervous that I babble (still happens sometimes, and it's just as mortifying every time), or if I'm not babbling I'm being a bitch, or saying the most inappropriate thing possible!