diff --git a/README.md b/README.md
index f8dc8dc..28f658e 100644
--- a/README.md
+++ b/README.md
@@ -10,6 +10,8 @@ on each yt-dlp invoke is unreasonable.
 
 `/home/mdlp/src` contains cloned git repo, `/home/mdlp/venv` is a python venv.
 
+Tip: to add track number to filenames, set `TRACK_FILE_TMPL="%(track_number)d %(track)S.%(ext)s"`
+
 ## nginx
 ```
 server {