If you want to achieve grey hair without using bleach then this video is a must watch. These days you can try any color you want without committing to bleach or permanent color.
The product used is Streaks N Tips Hair Color Spray. Check out the video:
This is temporary color so expect it to fade away but it is an awesome option for a night out or a special occasion. MissKenK killed the game with this one, I love it!