diff --git a/src/components/SiteHeader/SiteHeader.stories.svelte b/src/components/SiteHeader/SiteHeader.stories.svelte
index 771fbd8d..0a39750a 100644
--- a/src/components/SiteHeader/SiteHeader.stories.svelte
+++ b/src/components/SiteHeader/SiteHeader.stories.svelte
@@ -42,7 +42,7 @@
-
diff --git a/src/components/Theme/stories/docs/pattern.md b/src/components/Theme/stories/docs/pattern.md
new file mode 100644
index 00000000..a7743a4a
--- /dev/null
+++ b/src/components/Theme/stories/docs/pattern.md
@@ -0,0 +1,36 @@
+To use a background pattern or image, set the background colour property in your custom theme to `transparent`...
+
+```svelte
+
+
+
+```
+
+... then set your background image in global SCSS:
+
+```scss
+// global.scss
+body {
+ background-color: darkblue;
+ background-image: url('$assets/images/my-pattern.png');
+}
+```
+
+You may also want to override the background on the header nav if it conflicts with your background, especially the dropdown menu:
+
+```scss
+// global.scss
+// Main nav container
+.nav-container .inner {
+ background: darkblue !important;
+ // Dropdown menu
+ .dropdown {
+ background: darkblue !important;
+ }
+}
+```