Merge images/README.md with the style guide

- Update guidance to store images in GH repo
- Merge images/README.md with the style guide

contribute/anbox-style-guide.md

@@ -98,6 +98,187 @@ Use alternative text (or alt text) for images when visual details cannot be incl
 
 When writing alt text for images, consider the content, its context and purpose. It should accurately reflect the content and at the same time be concise.
 
+## Creating custom images
+
+Go to [`draw.io`](https://www.drawio.com/). 
+
+```{note}
+The use of `draw.io` is only a suggestion. You can create diagrams using other tools as long as it follows the design conventions listed below and is consistent with the appearance of the other diagrams used in this documentation.
+```
+
+Load custom shapes:
+
+1. Go to **File** > **Open Library from** > **Device**.
+2. Select the [`anbox-cloud-docs/images/anbox-drawio.xml`](/images/anbox-drawio.xml) file.
+
+Configure custom styles and colours:
+
+1. Go to **Extras** > **Configuration**.
+2. Paste the following configuration:
+
+```
+{
+  "defaultFonts": [
+    {
+      "fontFamily": "ubuntu",
+      "fontUrl": "https://fonts.googleapis.com/css2?family=Ubuntu"
+    }
+  ],
+  "defaultVertexStyle": {
+    "fontFamily": "ubuntu",
+    "fontSize": "15"
+  },
+  "defaultEdgeStyle": {
+    "fontFamily": "ubuntu"
+  },
+  "presetColors": [
+    "E95420",
+    "FFFFFF",
+    "000000",
+    "77216F",
+    "772953",
+    "5E2750",
+    "2C001E",
+    "AEA79F",
+    "333333",
+    "111111"
+  ],
+  "defaultColorSchemes": [
+    [
+      null,
+      {
+        "fill": "#E95420",
+        "stroke": "none",
+        "font": "#FFFFFF"
+      },
+      {
+        "fill": "#DEDBD8",
+        "stroke": "none",
+        "font": "#111111"
+      },
+      {
+        "fill": "#77216F",
+        "stroke": "none",
+        "font": "#FFFFFF"
+      },
+      {
+        "fill": "#772953",
+        "stroke": "none",
+        "font": "#FFFFFF"
+      },
+      {
+        "fill": "#5E2750",
+        "stroke": "none",
+        "font": "#FFFFFF"
+      },
+      {
+        "fill": "#2C001E",
+        "stroke": "none",
+        "font": "#FFFFFF"
+      },
+      {
+        "fill": "#AEA79F",
+        "stroke": "none",
+        "font": "#111111"
+      }
+    ]
+  ],
+  "defaultColors": [
+    "none",
+    "E95420",
+    "EB6536",
+    "ED764D",
+    "F08763",
+    "F29879",
+    "F4AA90",
+    "F5B29B",
+    "F6BBA6",
+    "F7C3B1",
+    "F8CCBC",
+    "FAD4C7",
+    "FBDDD2",
+    "FCE5DE",
+    "FDEEE9",
+    "772953",
+    "843E64",
+    "925375",
+    "9F6986",
+    "AD7E97",
+    "BB94A9",
+    "C19EB1",
+    "C8A9BA",
+    "CFB4C2",
+    "D6BECB",
+    "DDC9D4",
+    "E3D4DC",
+    "EADEE5",
+    "F1E9ED",
+    "77216F",
+    "84377D",
+    "924D8B",
+    "9F639A",
+    "AD79A8",
+    "BB90B7",
+    "C19BBE",
+    "C8A6C5",
+    "CFB1CC",
+    "D6BCD3",
+    "DDC7DB",
+    "E3D2E2",
+    "EADDE9",
+    "F1E8F0",
+    "5E2750",
+    "6E3C61",
+    "7E5273",
+    "8E6784",
+    "9E7D96",
+    "AE93A7",
+    "B69DB0",
+    "BEA8B9",
+    "C6B3C1",
+    "CEBECA",
+    "D6C9D3",
+    "DED3DC",
+    "E6DEE4",
+    "EEE9ED",
+    "2C001E",
+    "411934",
+    "56334B",
+    "6B4C61",
+    "806678",
+    "957F8E",
+    "A08C99",
+    "AA99A5",
+    "B5A5B0",
+    "BFB2BB",
+    "CABFC6",
+    "D4CCD2",
+    "DFD8DD",
+    "E9E5E8",
+    "AEA79F",
+    "B6AFA8",
+    "BEB8B2",
+    "C6C1BB",
+    "CECAC5",
+    "D6D3CF",
+    "DAD7D3",
+    "DEDBD8",
+    "E2E0DD",
+    "E6E4E2",
+    "EAE9E7",
+    "EEEDEB",
+    "F2F1F0",
+    "F6F6F5"
+  ]
+}
+```
+
+Always use font `ubuntu` and  the standard font size is 15pt.
+
+Use only the provided colours. See the colour palette at [`https://design.ubuntu.com/brand/colour-palette/`](https://design.ubuntu.com/brand/colour-palette/) .
+
+Once created, upload images along with their source files to the [images](/images/) folder of the documentation repository.
+
 ## Redirects
 
 Set up redirects in [`custom_conf.py`](/custom_conf.py) whenever a file path changes as it affects the URL of the page.