What do you do when a client can't decide between going blonde and going brunette? You give her both of course! However, mixing both colors can be tricky, as shown by Sadie Gray (@sadiejcre8s), BTC #ONESHOT Hair Awards Finalist and owner of Sadie Jean & Co in Santa Rosa, Calif. But don't let the number of steps stop you from achieving this gloriously blonde how-to. Sadie gave us all the details so you too can perfectly weave brown and blonde together. Check it…