Weapon random movement

Hi Everyone I am a bit new to scripting in and I have tried so many things but now I do not know which way should I go. I am using Neurosky headset to create a small application/game for neurofeedback training. What I would like to do is extend my FPS game with brainwave data. I would like to make my weapon move radomly (inaccuracy but movements like sniper scope movement/swing) and this would make the aimig much harder, and my idea is the more the player focuses the less this random movment is going to be. I just do not know how to start this inaccuracy script or which way is the best. Animations are not good, because I want to reduce this random movement in real-time. And if I am using perlin/noise and attach it to the camera I can not move forward anymore. Thanks joseph