It would entirely depend upon your type and simulator fit but it is fairly simple to do. I'm surprised there is no standard profile issued by your training department as the exercise can be interpreted and run differently depending on how you set it up.
We have an airspeed unreliable (asi failure for all three displays) which does the trick which if given in the climb makes for an interesting handling/non-normal management exercise. Volcanic ash is an interesting idea although it will of course give you the engine malfunctions which may or may not be desired. If you want to simulate af447 I'm guessing not.
Feel free to pm me