Wow, wasn't really expecting anyone to post in here, this is awesome.
EEEE, thats always the trick right? Well I did it two ways. First, measure measure measure yourself. Take measuring tape (perferably for cloth, that flexible ribbon with measurements on it kind and get any kind of relevant data on yourself. Then, start with a base piece. For instance with me I started with the shin piece.
I knew that from near the ground to a little bit above my knee was about 24 inches, or two feet. Since the Shin armor covers past the knee, and nearly touches the ground, this is the base measurement I wanted to make. I took 24 inches (I gave myself a little bit of cut incase I ran too big and had the shin scraping the ground every step I took) and converted it to mm. I got 605 mm. I then plugged this into pepakura designer as the height.
This also gave me a base scale of 27.65. So now you have a part scaled out right. But how do you get the others to line up and not have one piece be too big or too small, or even sure you made the right measurements Well theres a great tool called import. You can import muliple pep files at once and if the modeler designed it right, they will all line up to where they are supposed to be. So I measured up to my neck and converted that into mm and got around 1729 mm total, or 5'6 (I'm 6'2 total.) This matched around the same scale of 27.65 I had from the shin and so I knew I got the overal scale just about right. From there I printed out the pieces all at that set scale, now I don't have a huge chest piece and a tiny thigh etc. I'm uploading some pics now to show you what I mean, I hope this helps.
Thanks man.
Status update: The forearms are going up for paint tonight and my fiancee's rescue armor is almost done (still need to finish building the helm, painting most of the pieces and adding some parts to the hip area (this is about an 80% scratchbuild)). Our local comic shop has asked us to come out for free comic book day next Saturday as well as the Iron Man midnight release. Also a local venue I swear is mocking me by having a costume party this Friday and they put Iron Man on the damn cover of all the invites. Might just have to take a brief pause tomorrow night from working on this thing to show up.