The idea behind it is to aimbot without changing your view or making it seem like your view didn't change, then correct your movement so that you move
in the direction your 'fakeview' is.
If you're doing this in C++:
CHLClient::CreateMove
Won't change your view because you're modifying CUserCmd after CInput::CreateMove.
IClientMode::CreateMove
Return false to make it not change your view, return true to make it change your view.
If you're using Lua
Hook CalcView and CalcViewViewModel and set your own angles based off of mouse velocity (there's better ways but I havn't looked into it)
As for the movement fix, there's tons of code if you don't know how to do this.