Many people will first "skim read" your paper. This means they will look at the figures and read their captions. Hence, you need to embed the main messages in the figures in a manner that can be conveyed clearly and rapidly.

• When choosing the figures to put in your paper, analysis, synthesis, and discipline is needed.
• Polish and repolish every figure. 
• Make a simple schematic figure that illustrates the main point for the graphical abstract.
• Do not include any figures that do not carry a significant new message in the main text. You can always put supporting figures in the supplementary information (i.e. convergence tests, sanity checks, etc.).  
• Captions must be self-contained. Ideally, the reader should not refer to the caption to understand the figure. Hence, avoid acronyms, notations, parameter values, etc. 
• Begin the caption with a short title sentence that summarises the main point of the figure. Why are you including the figure in the paper? What do we really learn from the figure?
• If the reader has to work really hard to understand the figure they will quickly lose interest.
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