I explained how to make both border sizes in myself tutorial. In the tutorial I explain how to give the big border to create the small one.
https://gbatemp.net/threads/custom-theme-thread.377399/page-265#post-6724026
Users are only downloading tutorial 1. The correct thing is to download all the files.
Because the tutorial is divided into two parts the part 1 explains how to create the big border and part 2 explains how to create the small border. The first PSD file is used to create both textures.
I've even explained how to correct the icon alignment error in the texture. Because without this correction the texture icon is 1px above misaligned.