If, by your question, you mean to make an Ironman suit at home for cosplay then let me tell you I have tried making one with cardboard and its not at all easy. But its not impossible. I you are making a suit than it will be a commitment which could last for few months. So get ready.

I found out this youtube video if you are serious, watch this out: https://www.youtube.com/watch?v=8dy9tAhweeU

The only one who can teach you to make a real iron man suit is tony stark if u wanted to make a cos play suit as said by raj mehta above???? u could make it from cardboard or thermocol but it takes so much time and patience if u have them just give it a try

You have to become tony Stark for that
Or even a Bruce Wayne do

Well it is pretty much impossible without an arc reactor but of you are doing it for fun then it will still take lot of time to make a suit