(Note: This is based on Excel 2002, but it works basically the same way in all versions)
1. Enter the data from which you wish to generate a graph in two columns, with paired data in the same row. The data that will be plotted along the x-axis needs to be to the left of the data that will be plotted on the y-axis. For example, if you were making of plot of velocity vs. time, you would enter the time in the first column and the velocity in the second (or any other columns as long as the time data was to the left of the velocity data).
2. Highlight the two columns containing your data. You can highlight an entire column by clicking on the column letter or highlight just the cells with your data by clicking and dragging. You can highlight separated cells by holding down the CTRL key while you click.
3. Click on the Chart Wizard (the icon which looks like a bar graph) or click on INSERT à CHART.
4. Select the XY (Scatter) chart type, and then the chart sub-type which has no connecting lines between the data points.
5. Click NEXT.
6. You should see a small window showing a preview of your graph. Check the axes to see that you have the right data on the right axes, etc. If there is a problem you can click BACK or CANCEL and make corrections.
7. Assuming things look good, click NEXT.
8. The next window lets you input the graph title and labels for the axes. Enter these now. If you need to make changes later, you can. You can click on the Gridlines tab in this window to adjust the number of gridlines on each axis. Remember that if you are going to read values off your graph you will need enough gridlines to read your values with precision. You can also move or remove the legend by clicking on the Legend tab and checking the appropriate box. Normally, you won’t need a legend at all, but if you are plotting more than one data set on the same graph it is useful.
9. After getting the labels, title, gridlines and legend the way you want, click NEXT.
10. The next window asks you where to put the graph. Normally you want your graph to be on a single, full page, so choose the option that says “As new sheet.” You can name the sheet at this time if you wish.
11. Click FINISH, and you should see a single page with your graph.
12. At this point you probably want to do a little “cleaning up.” Excel likes to default to a gray background for the graph. This can make your data hard to read. To change to a white background (or some other color), right click on the gray area and choose “Format Plot Area.” Choose the AREA à NONE option for a white background. Click OK.
13. You can change other parts of the graph in a similar way. Right-clicking will generally open up an option box that will include formatting options. You can click on the title, labels, etc. to change them.
14. To add a best-fit line to your graph, single click on a data point to highlight the data set, then from the menu choose CHART à ADD TRENDLINE, or right-click on a data point and select ADD TRENDLINE. Under the TYPE tab select LINEAR and under the OPTIONS tab select Display Equation on Chart. Click OK. You may want to click and drag the equation (which gives you your slope and intercept) to a place on the graph where it is easily readable.