My advice: Wear cloth, a light head armor, and use your weapon of choice. Guaranteed to make money, and you'll be fine if you can block (which I assume you're not good at atm and/or a shielder), once you become a good fighter you'll learn to appreciate the cloth, and before you learn gameplay (note I'm assuming you're new to warband) regardless of your armor you'll not have a big/any impact in the battle.