Here are some tips that will help your readers quickly verify that your data supports your statements.
Tables are useful for recording the numerical results of your experiments or investigations. Plots may present some of the data in a better manner, but plots aren't as useful if the actual numerical results are needed.
Large tables that contain a lot of information, say the values of the control variables and the values of the results for the entire study, are useful for archival purposes, but they aren't ideal for making comparisons. Thus, such an archival table should be put in an appendix. For comparisons, you can place mini tables in the report body. If you are comparing two experiments that differ only by one control variable, e.g. temperature, then you can leave out the other control variables. The values of the other control variables can be placed in a note below the table if desired.
Studies have shown that readers more readily comprehend comparisons of two numbers if they are adjacent horizontally instead of vertically. Thus, each column should contain information for a case with a different variable in each row.
If you need to refer to a row or column number in your discussion, then make sure your table contains the row and column numbers on left and top, respectively. Numbered columns and rows are especially important if the table is large. Column numbers are still helpful even if the column contains case or run identifiers at the top, unless the case identifiers themselves are sequential.
Plots can readily convey a lot more information than tables. The danger is that the plot contains too much information...too many curves or curves that don't need to be shown together.
The axes should be labeled properly, including the units for the variables. The independent or control variables should be on the horizontal axis. Curves can be labeled on the plot or in a legend.
Plots look great in color and it helps the reader. There may be cases where a journal requests no color, but for internal reports, color is now acceptable. In the early days of copiers, black and white was the only option for copies. Now, color copies are readily available if needed. Most reports now are distributed electronically so color is available to all readers via the computer monitor.
There are some great books on ways to display data in alternative graphic formats. However, most of these formats are for non-engineering data, such as demographics involving geographical locations. For engineering, I continue to use simple, traditional plots. For 3D plots, I prefer contours instead of a true 3D surface. Although the surface may be impressive, the contour plots are more useful for presenting numerical information that can be easily read from the plot.
Grid lines should be included in plots that are intended to supply numerical values instead of merely a trend or comparison.
Numbering of Tables and Plots
Be sure to take advantage of the automatic numbering fields for tables and plots in your word processor. It makes inserting and deleting so much easier because all of the references get updated with the changes. When you reference a plot or table in the discussion, use a reference field so that it too gets updated when the table or plot number changes.