I can't tell you much, since we need to know the stats, exact skills etc. before we can give you a detailed describtion of what to do.
However, from my point of view, it looks like your weapon is your problem. Is it just a plain legend sword with eth/eth/ith in it? Because 600 2-h max damage at level 62 is not much, actually it's very low. Try to get a high damaging 2 handed sword of some kind, ccb for a start, those can be shopped for without too much difficulty.
As for your skills, be sure to have maxed out concentrate and battle orders. Battle orders is a synergy for concentrate, and it will add a lot of damage.
Try to max the other synergies for concentrate, can't remember them right now, but that would definately help. Or find out what your weapons is going to be, and then max the correct mastery for it. At later lvls, you probably would want to max shout as well, as it adds tons of defense...more than iron skin actually.
That's what I'm going to say to you as of now, hope you can fix him, at least get a better weapon
cya, Krime
