HELLO,
I would recommend a non ammonia color level 8,9 or 10. 10 being the lightest. It really depends on how much grey you have. By using a neutral blonde shade perhaps with a dash of gold in it you can enhance your grey by depositing tone. An added benefit in using a non ammonia color is additional shine and control of those often times, unruly grey hairs... there is no damage involved and very low maintenance,as the grow out is subtle. I hope this helps you
Tracey in Naples,FL