Ninja ZX10R, Sozius, sitting position

Hello dear ones, Yesterday I drove with my friend as Sozius on his ninja zx10r for the first time. Now I had a little bit of problems with the seat position or didn’t know where I should hold on to the brakes. Since I didn’t want to lean on my friend with full weight, I always supported myself at the front of the tank while braking, which, after a while, is animally on the poor. Do you have a tip? My friend said it was more pleasant for him. .. Well, besides, after a while I had severe neck pain due to the bent posture. Is this only due to the unusual posture?? Does this go away if you drive more often? Or do you have tips here? Unfortunately, as a passenger you can’t really sit upright, because you get the complete against wind. Do you have any advice. Thank you!