diff --git a/README.md b/README.md
index 792c9c5..38c0668 100644
--- a/README.md
+++ b/README.md
@@ -19,11 +19,6 @@ Homebrew
 
 To find out more [click here](https://github.com/extsoft/homebrew-insight).
 
-For development
----------------
-1. clone the repository
-2. run `./install.bash dev`
-
 Usage
 =====
 ```bash
@@ -38,3 +33,16 @@ clone
 add
 clear-local
 ```
+
+Development
+===========
+Installation
+---------------
+1. clone the repository
+2. run `./install.bash dev`
+
+Debug
+-----
+`export GED=1` to turn on the debug of `git elegant` execution.
+
+`unset GED` to turn off the debug of `git elegant` execution.
diff --git a/src/main/git-elegant b/src/main/git-elegant
index 6ccb56c..404aa6d 100755
--- a/src/main/git-elegant
+++ b/src/main/git-elegant
@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 set -e
-[  "$DEBUG" = "yes" ] && set -x
+[  -n "$GED" ] && set -x
 
 BINS=$(dirname "$0")