Add the diagram creation guidelines. (#3983)

* Add the diagram creation guidelines.

These guidelines include an SVG file with all the shapes and styles needed. The
steps to get someone started are meant to entice people to create their own
diagrams.

Signed-off-by: rcaballeromx <grca@google.com>

* Add InkScape to the spell checker exceptions.

Signed-off-by: rcaballeromx <grca@google.com>

* Add Google Draw version of the guide.

Signed-off-by: rcaballeromx <grca@google.com>

* Add steps to contribute Google Draw diagrams.

Signed-off-by: rcaballeromx <grca@google.com>

.spelling

@@ -234,6 +234,7 @@ initializer
 Initializers
 initializers
 injector
+InkScape
 int64
 interdependencies
 Interdependencies

content/about/contribute/creating-and-editing-pages/index.md

@@ -1,7 +1,7 @@
 ---
 title: Creating and Editing Pages
 description: Explains the mechanics of creating and maintaining documentation pages.
-weight: 30
+weight: 10
 aliases:
     - /docs/welcome/contribute/writing-a-new-topic.html
     - /docs/reference/contribute/writing-a-new-topic.html

content/about/contribute/diagrams/index.md

@@ -0,0 +1,53 @@
+---
+title: Diagram Creation Guidelines
+description: Provides assets and instructions to create diagrams for the Istio documentation.
+weight: 40
+keywords: [contribute,diagram,documentation,guide]
+---
+
+Welcome to the Istio diagram guide!
+
+The guide is available as an [SVG file](./diagram-guidelines.svg) or as a
+[Google Draw file](https://docs.google.com/drawings/d/1f3NyutAQIDOA8ojGNyMA5JAJllDShZGQAFfdD01XdSc/edit)
+to allow you to reuse the shapes and styles with ease. Use these guidelines to
+create SVG diagrams for the Istio website using any vector graphics tool like
+Google Draw, InkScape, or Illustrator. Please ensure that the text in your
+diagrams remains editable.
+
+Our goal is to drive consistency across all diagrams in our website to ensure
+diagrams are clear, technically accurate, and accessible.
+
+Keeping the text editable allows the community to improve and change the
+diagrams as needed.
+
+To create your diagrams, follow these steps:
+
+1. Refer to the [guide](./diagram-guidelines.svg) and copy-paste from it as
+   needed.
+1. Connect the shapes with the appropriate style of line.
+1. Label the shapes and lines with descriptive yet short text.
+1. Add a legend for any labels that apply multiple times.
+1. [Contribute](/about/contribute/github/#add) you diagram to our
+   documentation.
+
+If you create the diagram in Google Draw, follow these steps:
+
+1. Put your diagram in our [team drive](https://drive.google.com/corp/drive/u/0/folders/1jczscJueUBR3IOvH30q9HAZX0jC7GSyW).
+1. Once the diagram is complete, export it as SVG and include the SVG
+   file in your PR.
+1. Leave a comment in the MarkDown file containing the diagram with the
+   URL to the Google Draw file.
+
+If your diagram depicts a process, **do not add the descriptions of the steps**
+to the diagram. Instead, only add the numbers of the steps to the diagram and
+add the descriptions of the steps as a numbered list in the document. Ensure
+that the numbers on the list match the numbers on your diagram. This approach
+helps make diagrams easier to understand and the content more accessible.
+
+Thank you for contributing to the Istio documentation!
+
+{{< image width="75%"
+    link="./diagram-guidelines.svg"
+    alt="The Istio diagram creation guidelines in SVG format."
+    title="The Istio Diagram Creation Guidelines"
+    >}}

content/about/contribute/github/index.md

@@ -1,7 +1,7 @@
 ---
 title: Working with GitHub
 description: Shows you how to use GitHub to work on Istio documentation.
-weight: 20
+weight: 30
 aliases:
     - /docs/welcome/contribute/creating-a-pull-request.html
     - /docs/welcome/contribute/staging-your-changes.html

content/about/contribute/style-guide/index.md

@@ -1,7 +1,7 @@
 ---
 title: Style Guide
 description: Explains the dos and donts of writing Istio documentation.
-weight: 70
+weight: 20
 aliases:
     - /docs/welcome/contribute/style-guide.html
     - /docs/reference/contribute/style-guide.html