Help ¿Any tips for this type of pleating?

I am making my own victorian lampshade. While I wait for my frame to be done, I am practicing this pleating technique to decorate some panels. Do you have any tips for me? I am struggling to make the pleating even and my fabric keeps tugging in an awkward way. I know I have to keep practicing but if you have any recommendations for me, I could use some help! (image found in pinterest, credits to the owner)

https://preview.redd.it/2031qa1l5hbh1.png?width=720&format=png&auto=webp&s=a0c8e54f5a5e29a77ebed7c0284b132787f8a40f