I think what you are asking is how to make the control surfaces less sensitive. The simplest way is to look at the connecting geometry of the linkage. To reduce amount of throw. connect the clevis to the outermost hole (furthest from the hingeline) in the horn on the control surface, and connect to the servo at the innermost hole of the servo arm. This will make for very small deflections in most installations. Be sure you have enough movement to control the plane. The other major concept to deal with is to use a very light hand on the controls, very small movements. Overcontrol is a most common mistake new flyers need to overcome. We have all been there at one time or another.

Good luck.