The command hist creates a histogram for the specified variable based on Stata's default parameters.

Adding the percent command changes the unit on the y-axis to percent. In this case we specify that the y-axis is the percent of cases in the x variable falling within each bin

The graph is meaningless without a title. The command title("title") creates a title above the graph. Be sensible in your choice, a title that is too long will overflow from the histogram's box and be cut.

The command width(bin size) enhances the clarity of the graph by specifying a standard size for each bin. The larger the bin, the lower the definition of the distribution of data; the smaller the bin, the greater the precision, at a cost in clarity. Find the right middle ground between clarity and precision. start(start point) defines the starting point for the first bin. It helps the comparison across distribution and improves the legibility of the graph by making clear where each bin starts and ends (once the width is specified).

A title is not enough to clarify the meaning of the graph. Adding titles to your axes will make the nature of the data you are describing transparent. The commands xtitle("xtitle") and ytitle("ytitle") allow you to specify the exact unit of measurement of the variable you are describing. To improve readability further, you can rotate the ytitle horizontally. orientation(horizontal) rotates the title without reformating, which often results in the title overlapping the graph if it is longer than a word or two. To solve this problem, simply add quotation marks to break up the title, e.g., ytitle("line1""line2""line3", orientation(horizontal))

Once you have changed the width of each bin, it may be useful to change the labels on the axes to better match the distribution. The commands xlable(startpoint(increment)endpoint) and ylable(startpoint(increment)endpoint) do just that. Each one changes where the first label and last label will be, and the increments between the two points. Here to, be sensible in choosing a middle ground between precision and clarity. Note, you can add an angle command after specifying the position of the labels to change their orientation. angle(angleoforientation) changes the orientation with 0 corresponding to the horizontal positioning while 90 is vertical.

A good way to achieve precision without sacrificing precision is to add tick marks instead of more labels. It is just a matter of adding xtick (startpoint(increment)endpoint) and ytick (startpoint(increment)endpoint) which work the same way as the labelling commands.