Where to begin again, Pepakura to Foam

[VoidRunner]

Hi All, I've gotten amazing advice here before and I'm in need again.

I started on a Master Chief armour build over a year ago and I had to take a break from it for quite a while.
I got to the point that I've cut out and assembled the entire armour through Pepakura in card stock to make sure it scales correctly (only the left side for arms and legs)

Now I'm at a sticking point on how to start making progress again.
The helmet I'm pretty set on solidifying it with resin and fibreglass, then adding details with Monster Clay before creating a cast from it. How wear it is still a problem to work on, though I'll probably see if I can make the lower rims of the helmet flexible, or remove the back of the helmet, but I'm going off on a tangent.

It's the main armour I need advice on for progress.
In my mind I'm thinking that now it's assembled I should go around the entire armour with a marker and draw out the best seam lines, alignment marks and segments for transfering onto foam sheets. Before dismantling it again. Though I'm worried about making poor choices on the lines, forgetting angles that need to be cut, a whole range of things.

Thoughts, advice and experiences are very appreciated.

I haven't even started thinking about how it is all going to attach together...

 

[Coreforge]

This is just how I do it, but I usually go straight from the pepakura templates to foam. When unfolding, I try to keep pieces without sharp angles together and cut and sharp folds, as you can only get those by cutting and glueing, while it's easier to keep just bent or somewhat convex/concave as one piece and heatform it. For forgetting angles, I usually just have the model open in pepakura so I can look up how big angles are.

 

[VoidRunner]

This is just how I do it, but I usually go straight from the pepakura templates to foam. When unfolding, I try to keep pieces without sharp angles together and cut and sharp folds, as you can only get those by cutting and glueing, while it's easier to keep just bent or somewhat convex/concave as one piece and heatform it. For forgetting angles, I usually just have the model open in pepakura so I can look up how big angles are.

Thank you for that. I have thought about going straight from Pepakura to Foam but what puts me off is there are so many little pieces and folds all over the place. Do you have any tips or go to methods you find work well?

It's still a learning curve, I've just got to get hands on and try now.
Gotta keep reminding myself it won't be perfect first time.

 

[Coreforge]

With those little pieces I'd say it's probably easiest to assemble them out of paper so that you have a reference and then just freehand them out of foam, or, if you can, 3d print them and glue them to the foam.