We did vitamins first and I think it was a good choice, we started with Kids Natural Calm and that alone helped.
I tend to be low key. We've done epsom salt baths and now we do other vitamins. We've also reduced dyes, HFCS and things like that but there's not 100% eliminated. My sons tics aren't bad now, we can live with where they're at. We'll see where it takes us.
It does feel overwhelming at first but it helps to realize you don't need to do everything at once.