Examine the Distribution of the Data is the first method. Corresponding data points in the other variables are identified, allowing you to see one form of relationship. Normal probability plots are also provided. Using them, you may determine if the data is normally distributed. The probability plots provide a straight line in the case of normally distributed data.
Deviations illustrate variation from normal.
Compare the Columns is the second method. Boxplots and dotplots are used for the comparison. I really like about this add-in is the tutorial information provided. Figure 4 illustrates the tutorial box provided to explain the components of a boxplot. I'm sorry, but I find this to be a very simple concept, which others generally tend to complicate.