Can someone explains Gracie's visits?

[Elysian]

Okay, so I understand that I need to upgrade to the Home Center and that I will need to pass four fashion checks, but when does Gracie normally show up? Are there certain things I need to do/have done for her to show up?

 

[Stevey Queen]

I'm pretty sure it's random. She probably won't show up when it's raining.

What I wanna know is how you pass her fashion checks. I've never been good at that.

 

[TxAnt]

You can see here, how to pass the checks.
http://www.thonky.com/animal-crossing-new-leaf/gracie-fashion-check/

 

[JimmyJacobAC]

The "Home Center" is called T.I.Y