diff --git a/README.md b/README.md
index b299934..dd010ad 100644
--- a/README.md
+++ b/README.md
@@ -7,6 +7,8 @@ See ``docker-compose.yml`` (It is a template)
 ### Manual
 Prepare:
 ```
+apt update
+apt install ffmpeg -y
 pip3 install -r requirements.txt
 pip3 install ffmpeg_python-0.2.0-py3-none-any.whl
 ```