My hair is black right now, roots are growing back in, my natural hair is dark brown. Can i go blond 4 Sept?

I've always wanted to be full on blonde. I've had many highlights in the past like a dark red with lots and lots of blonde highlights so I looked sort of blonde. Right now my hair is black with my dark brown roots grown in about 3 inches. I want to go FULL blonde for a visit to my family in Sept. Maybe like a Kate Hudson type blonde, not quite Gwen Stefani kind of color. Will this be hard for me to achieve? What steps should I take NOW before going to the salon? I REALLY want to do this BAD so I can really surprise my mom! Thank you for your input! :o)