To start, a few important things: my hair has
never been cut short, aside from the bangs, which have been growing out for the past couple of years and are fairly non-present (I actually really dig the layered look they add). I've been blonde my entire life, either naturally, or (after college started) with the assistance of some fairly mild highlighters. How much I like the way I look pretty directly correlates with how light my hair color is. All of the highlighting I did at home with friends without any trouble, I didn't stick to any particular brand, either, I was hap-hazard with good results.
Starting around age 7, I've wanted white/silver hair. Two months ago I went to a salon for the first time and went for it. My hair filled two sinks, two hairdressers did an intense and amazing job bumping my entire head up to a very pale platinum, and then toning it silver. I've since gone in to have my roots fixed (at the same place) once.
I tone it myself. I want to fix the roots at home for a number of reasons: I'm a circus performer and will be doing some traveling/touring, so it helps to be able to maintain my looks on the go. BUT, I don't know much at all about using 40vol/hardcore bleach. My roots are virgin, my hair is naturally a dark ash blonde.
If anyone here has made their own (or their friends') hair WHITE/SILVER at home, I would reeaalllyy appreciate any advice and/or instructions about the bleaching process.WHEW, that was long. Here's shortly after it was first done:

Two and a half weeks ago:
