[gogo]

I've seen debates on this, but I was taught to use a cross hatch pattern when sanding...
noth south, east west, nw se, ne sw etc
as opposed to sanding in circles.

sand more, not harder.
harder tends to make it uneven because you really can't apply even pressure. not to mention you're elbow gets tired and starts to burn from the workout.

let us know how it turns out.