Probability Plot Correlation Coefficient Plot and Tukey lambda

[Allamarein]

Please see:
http://www.itl.nist.gov/div898/handbook/eda/section3/ppccplot.htm

I understood the aim of this chart, but I would find a step by step
procedure.
I suppose I have to find the correlation coefficient between the
sample of data and the respective values predicted by the Tukey
distribution.
I would use the "corrcoef" command in Matlab.
http://www.mathworks.com/help/techdoc/ref/corrcoef.html
I should repeat this procedure for several values of lamba in order to
draw the PPCC plot.
Maybe I should normalize by sample too:
Y = (X-m)/s
with m the mean value, s the standard deviation, X the array of
original data and Y the normalized data.

Is my procedure correct to draw PPCC with Tukey lambda distribution?