I guess it will depend on body weight (amount of insulin resistance) and amount of carb that you eat. For example if you inject to cover the carbohydrate in a meal then a starting regime might be 1u. for every 10g but it has to be individual and will require blood glucose monitoring to get it right. I think they like you to be at slightly higher than normal bg when you go onto insulin just to minimise hypo risk.
Hopefully some guys here will provide a more detailed description of their experience as this is just what I have heard (I am a type 1 and a volunteer in the diabetes world).