Drive with the mouse, it's much easier.
When making a right turn, make sure you are not right next to the curb or else it will be very difficult to make the turn. Keep your distance from the curb, and as others said inch up and you are about half way, and then turn the wheel accordingly.
OMSI 92 Deadhead to Spandau Freudstr - TimelapseI know its kinda hard to see but in the end you see me making that right turn onto Freudstraße
As for the joysticks, it's kinda hard to get a good steering wheel for OMSI as a lot of the steering wheels I've looked at were designed for racing and not for bus driving.. The steering will be off as many of the wheels have a maximum turning radius (no 5102 joke intended) of 1/2 to 1 rotation, while as you can see on OMSI you need a wheel capable of reaching 3 full rotations