Zbrush | Append, resize, rotate and increase subtool size

and under Subtool, Click on Append to add a new Subtool. Click on circle 3d to form the bottom of the skirt. Click on Circle3D Subtool layer to edit. Press W to activate Gizmo. Click on the red line to rotate Circle3D backwards.

Turn on transparency by clicking the button on the bottom right. Rotate it so that you are viewing from the top then click on it. Click on the blue arrow to move Circle3D lower. Click and drag inwards or towards the center of the yellow box, to scale down the skirt. Let’s increase the resolution by pressing CTRL or CMD D a few times. Update the polyframe lines by pressing Shift F twice. Turning it off and on again.