*Gamma sighs and casts Takeno a cold sideways glance*
Did you feel it at first, when I came around? The chill that is. There are several ways to force out your Persona. Two main ones.
First, concentration, if you focus on making it appear, and what you want it to do, your Persona should appear for you. Its far from easy though.
Second, emotion. As you may have noticed, I came here in a poor mood, so some of Shiranui's effects, the lingering chill, is leaking through without my intent. Then you rip off that mask you're wearing, and it should appear in full force.