Sergio,
To be honest ... I am not so good at 3D CAD

. My intention is to build the plane and post pictures of the build process. This will be much better than 3D CAD
ALW Phantom,
The 'lines' on the bottom of the wings plans are the formers + spacing for the canopy.
Your options are: build a balsa canopy or a positive for a mold.
My preference is going to a carbon fiber canopy. It should be fantastic on this bipe. Therefore, the mold would be my option. A transparent canopy should be fine too. It's just a question of weight, finishing, taste, time & money
The PDF paper size is at the correct size to build this plane. If you go to a print shop just ask to print at scale 1:1. If the younger person looks at you with that 'face' then you will be entitled to reply: 'what ? Don't you know how to print plans at scale 1:1 ?'[>:]