diff --git a/setup-docker b/setup-docker
index df73e34..07b237a 100755
--- a/setup-docker
+++ b/setup-docker
@@ -15,41 +15,58 @@
 # [1] rootless docker's documentation: https://docs.docker.com/engine/security/rootless/
 # [2] CMLab's rootless docker guideline: https://hackmd.io/@snsd0805/SkWMyB1ER
 
-echo -e -n "\033[44m[CML INFO]\033[0m "
-echo "Start setting up Docker service"
+
+# utils functions
+
+function print_info {
+	local msg="$1"
+	echo -e -n "\033[44m[CML INFO]\033[0m "
+	echo "$msg"
+}
+
+function print_err {
+	local msg="$1"
+	echo -e -n "\033[41m[CML INFO]\033[0m "
+	echo "$msg"
+}
+
+function run_command_check {
+	local status="$1"
+	local success_prefix="$2"
+	local error_prefix="$3"
+	if [ $status -eq 0 ]; then
+		print_info "${success_prefix}"
+	else
+		print_err "${error_prefix}"
+		exit 1
+	fi
+}
+
+# start
+print_info "Start setting up Docker service"
 
 # insert the username into /etc/subuid & /etc/subuid
 # setup-uid's source code is on https://gitea.snsd0805.com/snsd0805/CMLAB-Docker-Builder/src/branch/master/tool/setup_uid.c
 setup-uid
-
-if [ $? -eq 0 ]; then
-	echo -e -n "\033[44m[CML INFO]\033[0m "
-	echo "Inserted $(whoami) into /etc/subuid & /etc/subgid"
-else
-	echo -e -n "\033[41m[CML ERROR]\033[0m "
-	echo "failed to set subuid & subgid. Please contact us: unix_manager@cmlab.csie.ntu.edu.tw"
-	exit 1
-fi
-
+run_command_check $? "Inserted $(whoami) into /etc/subuid & /etc/subgid" "failed to set subuid & subgid. Please contact us: unix_manager@cmlab.csie.ntu.edu.tw"
 
 # Run install script provided by docker
-curl -fsSL https://get.docker.com/rootless | DOCKER_BIN=/tmp2/$(whoami)/docker/bin sh
-if [ $? -eq 0 ]; then
-	echo -e -n "\033[44m[CML INFO]\033[0m "
-	echo "Docker installed."
+if [ ! -d "/tmp2/$(whoami)/docker/bin" ]; then
+	curl -fsSL https://get.docker.com/rootless | DOCKER_BIN=/tmp2/$(whoami)/docker/bin sh
+	run_command_check $? "Docker installed." "failed to install rootless docker. Please contact us: unix_manager@cmlab.csie.ntu.edu.tw"
+	export PATH="/tmp2/$(whoami)/docker/bin:$PATH"
+	export DOCKER_HOST="unix:///run/user/$(id -u)/docker.sock"
+	echo "export PATH=/tmp2/$(whoami)/docker/bin:\$PATH" >> ~/.bashrc
+	echo "export DOCKER_HOST=unix:///run/user/$(id -u)/docker.sock" >> ~/.bashrc
+	print_info "We have add some environment variables in your ~/.bashrc"
 else
-	echo -e -n "\033[41m[CML ERROR]\033[0m "
-	echo "failed to install rootless docker. Please contact us: unix_manager@cmlab.csie.ntu.edu.tw"
-	exit 1
+	print_info "Docker has been installed. We skip this step."	
 fi
 
-echo "export PATH=/tmp2/$(whoami)/docker/bin:\$PATH" >> ~/.bashrc
-echo "export DOCKER_HOST=unix:///run/user/$(id -u)/docker.sock" >> ~/.bashrc
-echo -e -n "\033[44m[CML INFO]\033[0m "
-echo "We have some environment variables in your ~/.bashrc"
-
 # Link NVIDIA Container Runtime to Docker & change docker image's path
-mkdir /tmp2/$(whoami)/docker-data
+if [ ! -d /tmp2/$(whoami)/docker-data ]; then
+	mkdir /tmp2/$(whoami)/docker-data
+fi
 cat << EOF > $HOME/.config/docker/daemon.json
 {
     "runtimes": {
@@ -61,28 +78,25 @@ cat << EOF > $HOME/.config/docker/daemon.json
     "data-root": "/tmp2/$(whoami)/docker-data"
 }
 EOF
-if [ $? -eq 0 ]; then
-	echo -e -n "\033[44m[CML INFO]\033[0m "
-	echo "Linked NVIDIA Container Runtime & changed the data path."
-else
-	echo -e -n "\033[41m[CML ERROR]\033[0m "
-	echo "failed to link NVIDIA Container Runtime to Docker. Please contact us: unix_manager@cmlab.csie.ntu.edu.tw"
-	exit 1
-fi
+run_command_check $? "Linked NVIDIA Container Runtime & changed the data path." "failed to link NVIDIA Container Runtime to Docker. Please contact us: unix_manager@cmlab.csie.ntu.edu.tw"
 
 # restart docker
-echo -e -n "\033[44m[CML INFO]\033[0m "
-echo "Restarting Docker..."
-
+print_info "Restarting Docker & test..."
 systemctl --user restart docker && docker pull ubuntu && docker run --rm --runtime=nvidia --gpus '"device=0,1"' ubuntu:22.04 nvidia-smi
 
-echo -e -n "\033[44m[CML INFO]\033[0m "
-echo "These are 2 GPUs on this server."
-
-
-
-
-
-
+print_info "These are 2 GPUs on this server."
+print_info "Complete all install steps."
+print_info "If you have any problems, please contact us!"
 
+echo 
+echo 'CMLab Unix Manager'
+echo 'CMLab, National Taiwan University'
+echo 'Email: unix_manager@cmlab.csie.ntu.edu.tw'
+echo '            __  __     _             '
+echo '           / / / /__  (_)_ __        '
+echo '   __  ___/ /_/ / _ \/ /\ \ /        '
+echo '  /  |/  /\____/_//_/_//_\_\____ ____'
+echo ' / /|_/ / _ `/ _ \/ _ `/ _ `/ -_) __/'
+echo '/_/  /_/\_,_/_//_/\_,_/\_, /\__/_/   '
+echo '                      /___/   	   '