Sort the data from least to greatest
Find the median of the data set
Split the data into a lower half and an upper half
Find the median of the lower half to get the first quartile
Find the median of the upper half to get the third quartile
The second quartile is the overall median
For an odd number of values, exclude the overall median when splitting the data
For an even number of values, split the data evenly into two halves
Use the quartiles to summarize the data into four equal parts