Do some core strength building, that way when riding you can use your stomach to take the weight iff your arms 
Lol stomach to take the weight off your arms?
That`d be the erector spinae I think you mean
Some little tips from when I was learning.
1) MOST IMPORTANT. Alway always always look where you WANT to go! If you`ve over cooked it, dont panic, look and pull your face where you want to go and the bike will follow! Look at the wall/kerb/car bonnet where you dont want to go, and the bike will still follow!
2) Get familiar with the concept of balancing grip between inputs. What I mean is you only have a little contact patch on your ties, and exceeding grip (when your inexperienced) will more than likely see you on your ass. SO (in very simlified terms) if you are using 80% of your grip to brake, you only have 20% left for steering and visa versa, and if your using 60% of your grip still in a corner, you only have 40% to accelerate out. It will take you a while to get a feel for how much grip you have in any given situation. So best advice until you get a feel for that is seperate your inputs. Approach turn on brakes, reach desired speed and turn in point, realease brakes and turn (steady throttle), finish turn, accelerate. That way you have less chance of overwhelming grip while your learning.
Later when you have good feel for this you will be able to blend/balance shifting inputs allowing you to brake into turns etc.
These concepts helped me alot when I was learning my way around on an RS.
Hope that helps
