The first major problem in your build is the cardboard type you choose; the best is to use some 'for sale' signs or in my case I used advertise/promotional panels used mostly in food stores. Here is my build using my own templates ==>
Rafal Works Helmet (RWH) v2 Helmet Templates and Build - this thread contains the template files but also a generic step-by-step instruction to build your own helmet. If you want to use WOF's templates (which you already did), here are the best build threads made by AntMan ==>
First post, first WOF bukcet build - cardboard! and
AntMan's Second Cardboard Scratch Build. I hope these helps!