Tell readers in the text what they
are supposed to get from a figure. That will help the readers focus on
the right points. It will also help in electronic publication, because
many people don't pull up figures to avoid the slow process of loading
the files.
Captions: A short descriptive caption should distinguish this figure from all others in the manuscript. The caption will appear in bold type and end with a period. If there is more to be explained than what is included in that, give the explanation as a non-bold sentence after the short title.
Comparisons: If there's a standard value for comparison, like compliance levels, make a dashed line across the graph to show where that is, so it's immediately obvious which values are above and below that level.
Complexity: Don't retain grids across graphs, unless you're making some point with it. If the grid is necessary, make the grid lines thinner or less bold than the data lines.
Labeling: Use upper- and lower-case type, not all capitals.
In labelling axes on graphs, use parentheses to set the unit off from the description.
Label important events in the data. For instance, for a time series that includes a spill that would affect sample content, label the time when the spill was. Use the names or abbreviations for the month names (with year breaks marked), not the length of time since some date, no matter how important that original date might be.
Label with words rather than codes as much as possible to save readers a step in interpreting what you're telling them.
Multiple figures: If the manuscript has a number of similar figures, use the same base (whether axes on a graph or the base drawing for a map) on all, so that the only thing that changes is the data, making comparison easy.
Photos: Use black-and-white prints for print publications, not color slides. The resolution that is so good in a slide is lost on paper.
Referring to figures: Spell out "Figure 1" in text (as part of a sentence or in parenthetical reference) and in captions. To refer to more than one figure, follow these conventions:
• (Figures 1, 2)
• (Figure 1A,B)
• (Figures 1–4).
Showing contrasts: Avoid Op Art juxtapositions of hatching. Shades of gray get the message to the 10% of people who are color-blind and so are preferable to color.
Contrasts in line weight should correspond to contrasts in meaning. Heavier lines should represent data, because they're what's important about the figures.
Types of figures:
Use graphs rather than bar charts if you can, to get more data into the
space. If several sets of data appear on one graph, use different-shaped
symbols (also solid and open); if possible, also contrast lines connecting
them (solid, dashed, dot-dashed).
