You should start with it deflected and return to neutral as the airspeed increases so that you leave the runway wings level.
Thats not what boeing say. I see quite a few pilots starting with it already deflected and working backwards to somewhere thats hopefully right. If you do it like the book says it works nicely, you never end up with too much aileron. Do you ease off the aileron as the airspeed increases and then during rotation change direction and increase the aileron input again in order to maintain the wings level during rotation?