On the second night, I went big on the ice very big. I found the biggest, deepest oven tray I could fit in the freezer, filled it with water, and left it there all day.
The Snoo is a smart bassinet that plays white noise and rocks your baby, ramping up the intensity if your baby keeps crying. I have heard from friends that it does not work for every baby, but when it works, it really works - and you have truly magical moments when it successfully puts your baby to sleep.