When Livi was a baby and would cry all the time, I got a lot of advice, both solicited and not, on how to calm and soothe her. I would also search online for anything that might do the trick and give us a break.
As a result, we tried a lot of different techniques, gadgets, and baby equipment. Some of it didn’t work; some made a (slight) difference. But we also found a few ways that really worked for us. I will cover both, the hits and the misses. High need babies are so unpredictable; what didn’t work for us, may just be what you are looking for.