What are the general rules for constructing diagrams?

Some of the general rules for constructing diagrams are as follows:

1. Attractive and effective: The diagram must be attractive and effective in communicating the required information.

2. Title: Diagrams must bear proper headings. A heading must be simple, short and informative.

3. Proper Size: Diagrams must suit the size of the paper, it should be neither too big, nor too small.

4. Proper Scale: Before making a diagram its scale should be properly determined and indicated as well.

5. Use of signs and colours: Diagrams must carry some signs on the nature and classification of information. Colours may be used to indicate different aspects of diagram.

6. Less use of words or numericals: In diagrammatic presentation of data one should make use of minimum number of words and calculations.

7. Footnote and Index: In case any feature of the diagram has not been adequately made clear footnote should be given. Different types of lines or shades should be given so that the reader can easily understand the diagram.

8. Simplicity: Diagrams should be simple as far as possible so that the reader can understand them clearly.