diff --git a/README.md b/README.md
index deb47d7..0d16308 100644
--- a/README.md
+++ b/README.md
@@ -20,3 +20,37 @@ curl https://raw.githubusercontent.com/oae/gnome-shell-extensions-sync/master/in
 2. Create a new token from [here](https://github.com/settings/tokens/new). Only gist permission is needed since we edit the gists.
 3. Open extension settings and fill gist id from first step and gist token from second step.
 4. Enjoy!
+
+## Notes
+
+* Downloading from gist will do 3 things.
+  - It will remove all extensions that are not exist in the gist.
+  - It will install extensions that are listed in gist and update their settings.
+  - It will update all the settings of installed the extensions.
+  
+* Uploading to gist will dump all the settings of the installed extensions(enabled/disabled) and put them in the gist with the below structure
+```json
+{
+  "description": "Extensions sync",
+  "files": {
+    "syncSettings": {
+      "content": {
+        "lastUpdatedAt": "time",
+      }
+    },
+    "extensions": {
+      "content": {
+        "extension1": {
+          "schema1": "schema1 settings",
+          "schema2": "schema2 settings",
+        },
+        "extension2": {
+          "schema1": "schema1 settings",
+          "schema2": "schema2 settings",
+        },
+      }
+    }
+  }
+}
+```
+