diff --git a/(EN)-Customization.md b/(EN)-Customization.md
index 5948b84..35766b9 100644
--- a/(EN)-Customization.md
+++ b/(EN)-Customization.md
@@ -1,5 +1,11 @@
 # Customization
 
+Table of contents:
+- [Description](#description)
+- [Instructions](#instructions)
+- [Examples](#examples)
+  - [API encryption](#api-encryption)
+
 ## Description
 This project adds lots of functionalities to your NSPanel and we are constantly adding new features based on user's feedback. However, you might have some specific case that are not included on the current implementation or is not a common case for other users.