diff --git a/README.md b/README.md
index 06df4ea..66797f9 100644
--- a/README.md
+++ b/README.md
@@ -19,6 +19,12 @@ Assuming `python3` is already installed, you can use the following command to in
 pip3 install csv numpy sounddevice
 ```
 
+If you need the GUI, additionally install PySimpleGui
+
+```bash
+pip3 install PySimpleGui
+```
+
 After that, simply run `python3 offitracker.py` and enjoy. The command can also take a path to a file as a parameter if you wish to use your shells autocompletion.
 
 ____