It's important to layout tables and figures correctly, with clear labels, titles, legends and / or captions. Figures can include graphs, photographs, drawings or maps (anything visual that isn't a table.)
Top tips!
- Figures and tables should be self sufficient - if they are read independently the reader should understand it from the represented data and accompanying legend or caption
- They should be numbered in separate series eg. Figure 1, Figure 2, Table 1, Table 2 etc and numbered in the order in which you refer to them
Tables
- Tables should have a title that describes the contents of the table
- If required, clarifying information can be added in a footnote (underneath your table)
- Contents of a table should be concise
Figures / graphs
- Should have a legend underneath with the Figure number and a description / caption of the data shown
- Use space efficiently in graphs
Abbreviations
- Where you are abbreviating something, if it is something that is not in common science use, define the abbreviation once and after that use the abbreviation only.
Successful Scientific Writing by 
Communication Skills for the Biosciences by 
Writing Papers in the Biological Sciences by 
A short guide to writing about biology 9th ed by