diff --git a/app.py b/app.py
index 5011caa..acced2f 100644
--- a/app.py
+++ b/app.py
@@ -93,7 +93,7 @@ END:VCALENDAR
 
 # Usage example
 if __name__ == "__main__":
-    logger.add("output.log", backtrace=True, diagnose=True)
+    logger.add("output.log", backtrace=True, colorize=True, diagnose=True)
 
     if len(sys.argv) != 7:
         logger.exception{"Usage: python3 app.py <caldav_url> <calendar_name> <username> <password> <ra_api_key> [OPTIONAL] <ra_username>"}