Graphs should be done using Microsoft Excel or similar software.
Open Office also provides a spreadsheet software that is similar to Excel.
On Mac, Numbers is a spreadsheet software that can also do the job.
Each graph should be numbered and have a descriptive title. Each axis should be clearly identified with the proper dimension and units.
Your data should use approximately 80% of the area of the graph, and the graph should be no smaller than 1/2 a page.
Graphs should show all the experimental points, error bars and a trendline if possible.
Obtain from a graph all the required information, such as slope, intercept, etc. Show these results on the graph itself or just after the graph. You may write additional information on graphs, by hand.