L12 Diagrams Project

title: "Technical Diagrams — Complete Project" weight: 12 description: "Apply everything you learned about technical diagrams in a comprehensive project: plan, create, review, and publish a complete set of diagrams for a real documentation page." date: 2026-06-28 lastmod: 2026-06-28 tags: [technical-writing, diagrams] }

The technical diagrams project applies every skill from this course: choosing diagram types, creating Mermaid diagrams, using Excalidraw and Draw.io, and following best practices for a complete documentation page.

In this lesson, you will combine all previous lessons into a single end-to-end project producing a documentation page with multiple diagram types.

What You'll Learn

You will apply diagram type selection, Mermaid creation, Excalidraw sketching, Draw.io architecture diagrams, and best practices to create a professional documentation page with integrated visuals.

Why It Matters

Theory without practice is worthless. This project forces you to apply every skill you learned. The documentation page you create becomes a portfolio piece demonstrating your visual communication ability.

Project Steps

Step 1: Choose a System to Document

Select a system you know well: DodaZIP, Doda Browser, or any open source project. You will create multiple diagrams for a single feature.

Step 2: Plan Your Diagrams

Create a diagram plan listing which diagrams you will create and which type each will use:

• High-level architecture (Draw.io)
• Key workflow (Mermaid flowchart)
• API interaction (Mermaid sequence)
• Data model (Mermaid class)
• Timeline (Mermaid Gantt)

def create_diagram_plan(feature_name):
    """Plan diagrams needed for documenting a feature."""
    return [
        {"type": "architecture", "tool": "Draw.io", "purpose": "System overview"},
        {"type": "flowchart", "tool": "Mermaid", "purpose": "User workflow"},
        {"type": "sequence", "tool": "Mermaid", "purpose": "API interaction"},
        {"type": "class", "tool": "Mermaid", "purpose": "Data model"},
        {"type": "sketch", "tool": "Excalidraw", "purpose": "Wireframe"},
    ]

plan = create_diagram_plan("DodaZIP compression")
for p in plan:
    print(f"{p['type']}: {p['purpose']} ({p['tool']})")

Step 3: Create Each Diagram

Create all 5 diagrams. Follow the style guide from Lesson 11. Ensure consistent colors and fonts.

Step 4: Write the Documentation Page

Write a documentation page that integrates all diagrams:

• Introductory paragraph for each diagram
• Diagrams placed near the relevant text
• Alt text for every diagram
• Proper headings and structure

Step 5: Review and Publish

Review against the quality checklist:

• Correct diagram types used
• Consistent styling
• Accessible colors and fonts
• Alt text provided
• Diagrams match accompanying text

Teacher Mindset

This project is your portfolio piece. A documentation page with well-designed diagrams demonstrates a skill that most technical writers lack: the ability to communicate visually. When hiring managers see your diagrams, they imagine you creating the same quality for their documentation. Take the time to make each diagram clear, consistent, and correctly typed.

Common Mistakes in the Project

1. Creating All Diagrams in One Tool

Each tool has strengths. Mermaid for text-based, Draw.io for cloud architecture, Excalidraw for sketches. Use the right tool for each diagram.

2. Diagrams That Do Not Match the Text

The text says one thing, the diagram shows another. Verify alignment. The diagram should reinforce the text, not contradict it.

3. No Consistent Styling Across Diagrams

Architecture diagram uses blue, flowchart uses green, sequence uses red. Apply the same color palette to all diagrams.

4. Skipping Alt Text

Alt text is required for accessibility and SEO. Every diagram needs descriptive alt text that conveys its content.

5. Publishing Without Peer Review

A second pair of eyes catches errors you missed. Ask a colleague to review the page and diagrams before publishing.

FAQ

Mini Project

This lesson is the mini project. Complete all steps: plan 5 diagrams, create them using the appropriate tools, write a documentation page, and publish it. Write a 300-word retrospective on what you learned.

What's Next