How do i use flasks?

[Benny B]

Playing with gamepad.

[Heroic]

you have to put them in your quick inventory slots, when you are in the fight and you slow-mo the game, you can chose between the skills, with LT and RT you can switch though the command rings, the flasks are one of them.

before you can use flasks, you have to fill them up with the things you want (healing etc) at a merchant.

[Dies Irae]

potion merchants, herbalists, innkeepers, so on. The ones that obviously sell consumables.