I'm not very good with low-poly, but I can give it a shot if I had a base mesh to start with.
You could start from the most easy armor -
Robe. There is some pictures which could help you.
here's some useful information for 3D modelling in FO:
Bod - body, Fee - boots, Han - gloves, Hea - helmet, Sho - shoulders. These parts are made as separate objects, and if you will be combining it, you should do it without of bones, otherwise you could mix up something. And when you will be releasing a scene from combined elements, don't forget which element was there at the beginning and which one just for correct combining, or you could lost connection of armor to bones, which would make your work useless.
For creation of armor, you'll need this file - ATR_Hum***_BodPrisonSuit.max (leather armor), ATR_Hum***_BodVaultSuit.max (metal armor, combat armor). where *** - is a gender and constitution. F-female, M-male, Fat-heavy Nor-normal, Str-tendinous, Wir-thin. For example, ATR_HumMStr_BodVaultSuit.max - is a vault suit, for tedious constitution, male. Thus, for each king of armor you should make an 8 variants of armor, though it's not that difficult as it sounds. Main work is to make two normal models for each gender and after that the critter (Fat, Str, Wir) are combined (Import->Merge) with the scene and part of model are joint together, to close bulging parts of a critter (don't forget to delete a critter after the work are finished). After that, the scene are saved with fitting name.
Here's the example of completed armor:
All necessary files could be downloaded hereGood luck with it.