I would never mess around with a whizz wheel or any other similar tool in the cockpit. Get the wind arrows marked on your map along with max drift. Make yourself a circle on a piece of paper and divide the circle in 4 slices with two lines. Mark the slice lines with
15deg= 1/4
30deg = 1/2
45deg=3/4
60deg= Full
This estimations is all you need for diversions.