Originally Posted by drisko

One thing that helped me get smoother shifts is putting slight "pressure" on the shift knob in the direction you want to shift. The transmission will not let you shift until the clutch disengages. Do not use force, just light pressure.

Doing this will ensure that the shift lever starts moving into the next gear as soon as it is mechanically possible. It seems to make less noise when I do it this way, not sure why (maybe because the revs drop cleanly as the next gear engages).