It's easier to make a good build after you get more bonus points, that are earned with achievements (presumably in Ironman mode). You can get more perk, skill and stat points with it, plus food.
After that you need good physical stats (Strength, Agility, Endurance, also Perception rank 5 is useful to see next enemy stance and more). You can use perk points to get more stats. Sunderer perk can be learned when you get more levels to beat armored opponents.
Good armor, including stat raising armor from second town, also will benefit you, and a weapon. Gold is not that hard to get by completing quests in brothel and the one that starts on town square.