diff --git a/README.markdown b/README.markdown
index 0cbea72c9..9fae9e4b1 100644
--- a/README.markdown
+++ b/README.markdown
@@ -154,6 +154,8 @@ If you have many functions that go well together, you can put them as a `XYZ.plu
 
 If you would like to override the functionality of a plugin distributed with Oh My Zsh, create a plugin of the same name in the `custom/plugins/` directory and it will be loaded instead of the one in `plugins/`.
 
+If you want to override a theme or use your own, make sure to name it `XYZ.zsh-theme` not `.zsh`.
+
 ## Getting Updates
 
 By default, you will be prompted to check for upgrades every few weeks. If you would like `oh-my-zsh` to automatically upgrade itself without prompting you, set the following in your `~/.zshrc`: