Update README

README.md

@@ -1,2 +1,19 @@
 # eid-image-extractor
-A simple python script to extract the image from a Belgian E-ID card
+## Introduction
+This is a small python script to extract the image from a Belgian electronic identity card.
+
+## How to install
+Before running this script you will need a few dependencies, notably, python 3, pip3 and the python module [eidreader](https://github.com/lino-framework/eidreader).
+
+To install eidreader you will also need to have ```swig``` installed. On an Arch system, the installation looks like this:
+```
+sudo pacman -S python3 swig
+sudo pip install eidreader
+```
+
+## How to use
+After you installed the dependencies, you can just run the script:
+```
+python3 eid-image-extractor.py
+```
+After this, if everything went well, you will see a file with the name ```{NATIONAL_NUMBER}.jpeg``` next to the script.