Tips for Drawing UML Diagrams

Here are some general guidelines for Unified Modeling Language Diagrams based on - The Elements of UML Style - by Scott W. Ambler

Do not use crossing lines. If you need to use crossing lines, depict them as a jump.

• No diagonal or curved lines.
• Use the same size for all symbols and arrange them symmetrically.
• Use white space in diagrams. It improves readability.
• Organize diagrams left to right, top to bottom.



• No visual noise ! Just show only what you need to show.
• Always prefer popular notation over cryptic notation.
• Split large UML diagrams into many smaller ones.
• Focus on content first, appearance second. Prefer single-page diagrams.
• Use notes to describe a UML diagram.
• Use conventions for diagram legends.
• Apply consistent, readable fonts.
• Follow effective naming conventions.
• Prefer common domain terminology in names.
• Apply specific language naming conventions on design diagrams.
• Use question marks to indicate unknowns. Use consistent colors for elements.
• Left-justify text in notes.
• Name stereotypes in <<graphical use interface>> and <<GUI>> format.
• Prefer naming conventions over stereotypes.
• Think twice before introducing a new stereotypes and use stereotypes consistently.
• Prefer notes over OCL or ASL to indicate constraints.
• Use strong verb to indicate action ! (for Use case modeling)