This weird gather...THING

[Chibi Ice Wolf]

I need some help on my Princess Garnet costume. I really want to do the gathered lifted up part in the front, but I'm not sure how, nor even what it's called. I'm sure there's a sewing term for it and I could search it up if I knew what it was. ;p I attached a picture to show what I'm talking about. It looks like there is a gathered part in the center pulling the fabric up. I think I've seen this done before and it looked like it could be an elastic in casing but I'm not sure. Any help muchly appreciated.

[melcat]

Do you mean the very bottom? - I don' think that's gathered - It looks cut.

[Sizzles]

theres something i saw that's similar to that. your supposed to:

Gather up each side along the center tier by sewing a vertical line along the length of it. Pull up the fabric and stitch a few times to hold it in place.