diff --git a/README b/README
index a84bc9b..e18294d 100755
--- a/README
+++ b/README
@@ -1,10 +1,10 @@
-tty-clock usage : tty-clock [-option]
+usage : tty-clock [-sctrvih] [-C [0-7]] [-f format]
     -s            Show seconds
     -c            Set the clock at the center of the terminal
-    -C <num>      Set the clock color
+    -C [0-7]      Set the clock color
     -t            Set the hour in 12h format
     -r            Do rebound the clock
-    -f <format>   Set the date format
+    -f format     Set the date format
     -v            Show tty-clock version
     -i            Show some info about tty-clock
     -h            Show this page