I'm probably overlooking something obvious here. How do I use the Mount vanity abilities with a PS4 controller?

I can't find a way to open the pet bar without going into the menus and manually turning it on/off. Then when the pet bar is up it's in the horizontal bar format so I can't use the controller hot key's to access the ability and I can't click and drag or assign the ability from anywhere to my cross-hotbar. What am I missing?

The only solution I've found so far is to attach a mouse/keyboard...