In Splatoon2, of course you get Super Sea Snails by:
get one when you level up a ranked level, eg B to B+
get 20 or so if you play in a Splatfest
and you can use Super Sea Snails in aid of building equipment sets to
make a slot in gear
reroll a full gear
But how do you know how many Super Sea Snails you have?!
I cannot find this info anywhere!