Adds instructions for invalidating the CloudFront cache

README.md

@@ -1,2 +1,18 @@
 # personal-website
 Joe Carstairs' personal website
+
+## Invalidating the CloudFront cache
+
+When you update pages, you’ll need to invalidate the CloudFront cache in order
+for CloudFront to serve the new versions before the caches expire (which could
+be a while). Here’s how to do it:
+
+1. Go to the CloudFront console
+2. Select the distribution for this website
+3. Go to the Invalidations tab
+4. Add a new Invalidation
+5. Include all pages you’ve updated
+  - Use the relative URL, not the filepath, e.g. "/blog/" not "/blog/index.html"
+  - Include the trailing "/" or it won’t work
+  - You can use wildcards to make life easier, e.g. "/blog/2024/01/29/*"
+