yeah, I usually use lower ceiling for the coxy feeling!

- //wand to get the axe which allows you to do such things :)
- left click on a block to select it as "pos1"
- right click on another block (or the same one if you just wanna edit that) to select it as "pos2"
- //set 78 to replace the blocks you selected with snow layers, just like he did :)

If you want more snow layers, just type //set 78:(number of layers you want)
Just remember that it will always count one more layer than number you wrote. So as an example if you want 5 layers of snow you have to type //set 78:4
Hope it helped :)