diff --git a/README.md b/README.md
index 29520b0..181cc38 100644
--- a/README.md
+++ b/README.md
@@ -8,33 +8,37 @@ Requirements
 
 + RHEL/CentOS/Scientific
 
-xexecscript(*.sh)
------------------
-
-Run SCRIPT after distro installation finishes.
-Script will be called with the guest's chroot as first argument, so you can use `chroot $1 <cmd>` to run code in the virtual machine.
+Usage
+-----
 
-copy.txt/postcopy.txt
----------------------
+```
+$ add-book.sh <book-name>
+```
 
-Read `source dest` lines from FILE, copying source files from host to dest in the guest's file system.
+```
+$ run-book.sh <book-name> <book-name> <book-name> ...
+$ CHROOT_DIR=/               run-book.sh <book-name>
+$ CHROOT_DIR=/path/to/chroot run-book.sh <book-name>
+```
 
 Getting Started
 ---------------
 
-Add a new book.
+### 1: Add a book
 
 ```
 $ ./add-book.sh untitled
 generated => untitled
 untitled
-untitled/xexecscript.d
-untitled/xexecscript.d/untitled.sh
 untitled/copy.txt
 untitled/guestroot
+untitled/xexecscript.d
+untitled/xexecscript.d/untitled.sh
 ```
 
-`untitled/xexecscript.d/untitled.sh` is a sample execscript.
+`untitled/xexecscript.d/untitled.sh`:
+
+Script will be called with the guest's chroot as first argument, so you can use `chroot $1 <cmd>` to run code in the virtual machine.
 
 ```
 #!/bin/bash
@@ -52,6 +56,28 @@ chroot $1 $SHELL -ex <<'EOS'
 EOS
 ```
 
+`untitled/copy.txt`:
+
+Reading `source dest` lines from FILE, copying source files from host to dest in the guest's file system before running execscript.
+
+```
+guestroot/etc/hostname /etc/hostname
+```
+
+### 2: Run the book
+
+Run the book in `CHROOT_DIR`(default is `/`).
+
+```
+$ sudo CHROOT_DIR=/path/to/chroot ./run-book.sh untitled
+```
+
+If you want to run the book on a host, you can set '/' to `CHROOT_DIR` like this.
+
+```
+$ sudo CHROOT_DIR= ./run-book.sh untitled
+```
+
 Contributing
 ------------
 
diff --git a/add-book.sh b/add-book.sh
index 9129bdb..240b5db 100755
--- a/add-book.sh
+++ b/add-book.sh
@@ -3,6 +3,9 @@
 # requires:
 #  bash
 #
+# usage:
+#  # add-book.sh <book-name>
+#
 set -e
 set -o pipefail
 
diff --git a/run-book.sh b/run-book.sh
index 22e50b8..8e8e247 100755
--- a/run-book.sh
+++ b/run-book.sh
@@ -4,11 +4,11 @@
 #  bash
 #
 # usage:
-#  # run-book.sh <name>
-#  # run-book.sh <name> <name> <name> ...
+#  # run-book.sh <book-name>
+#  # run-book.sh <book-name> <book-name> <book-name> ...
 #
-#  # CHROOT_DIR=/               run-book.sh <name>
-#  # CHROOT_DIR=/path/to/chroot run-book.sh <name>
+#  # CHROOT_DIR=/               run-book.sh <book-name>
+#  # CHROOT_DIR=/path/to/chroot run-book.sh <book-name>
 #
 
 ### functions