Hey there, welcome to the 405th.
There's a lot of stickies in the noob and creation forums that cover on how to get started. Please understand that there are a lot of people coming in here looking for help, so if it's just getting started from the basics, the best way is to read the stickies. If you have any specific questions, there's even a sticky listing members you can PM questions to!
Glad to hear you're starting on something smaller, like bracers, instead of the helmet.
Also, the important thing about the paper isn't the size (you can move things around in pepakura to fit most paper sizes, and there's a sticky on that also). The important thing is that you're using something that's at least as sturdy as cardstock. I'm guessing that might be your problem since you're complaining about it being too 'soft'. Make sure you use thicker paper such as cardstock so that when you get to the step where you put resin on it, it won't warp under the weight.
Just take the time to lurk, read through all the stickies you can, and you'll do fine. There's a lot of information on these boards, you just have to be willing to look for it.
Again, welcome to the boards!