diff --git a/cangrow.sh b/cangrow.sh
index daa3d99..5da59dc 100755
--- a/cangrow.sh
+++ b/cangrow.sh
@@ -12,6 +12,11 @@ ACLI_CMD="$ACLI --config-file arduino-cli.yml"
 
 function help() {
 	echo "$0 [setup|build|upload|webupload|monitor]"
+	echo "setup: setup build environment, download arduino-cli, install all dependencies for arduino ide"
+	echo "build: build firmware binary. will be saved into build/"
+	echo "upload: upload firmware by serial connection $TTY"
+	echo "webupload: upload firmware with webupload to $IP"
+	echo "monitor: serial monitor $TTY"
 	exit 1
 }