Update index.html.md

sites/handbook/source/handbook/marketing/corporate-marketing/social-marketing/admin/index.html.md

@@ -268,3 +268,11 @@ To tag a post after its been published:
 1. choose the `post performance` report
 1. use channel and publishing date filters to find the posts you're looking for
 1. click the outline of the tag icon 🏷, select the tag(s) for the post; the tag icon will now be blue to indicate there are tags added
+
+## Other administrative items
+### Social channel colors
+Please use the following hex colors to represent the channels in reports, in charts, or when calling it out in plain text. 
+- Facebook - #1778F2
+- Insta - #8A3AB9
+- LI - #0E76A8
+- Twitter - #1DA1F2