update installation guide

getting_started/installation_guide.md

@@ -1,10 +1,21 @@
-## Check existing installation
+We need to install the **Python interpreter** first! 
 
-We need Python first! 
+!> For our study group, we will be using `Python 3`, preferably >= `Python 3.6`.
 
-!> For our study group, we will be using `Python 3`, preferably >= `Python 3.6` :)
+You also need to have a **text editor** to write your code in. This can be (but not limited to) one of the following:
+
+* [Atom](https://atom.io)
+* [Gedit](https://wiki.gnome.org/Apps/Gedit)
+* [Notepad++](https://notepad-plus-plus.org)
+* [Sublime Text](https://www.sublimetext.com)
+* [Visual Studio Code](https://code.visualstudio.com)
+
+
+
+## Check existing Python installation
+
+To check if Python is already installed in your system, open your terminal or command prompt.
 
-To check if Python is already installed, open your terminal or command prompt.
 - For Windows users, search for `cmd`
 - For Linux and Mac users, search for `terminal`
 
@@ -30,12 +41,60 @@ Python 3.6.0
 
 ## Tutorial
 
-For a detailed installation process, please [use this tutorial](https://tutorial.djangogirls.org/en/python_installation/).
+For a detailed installation process, you can [use this tutorial](https://tutorial.djangogirls.org/en/python_installation).
+
+### Windows and OS X
 
-!> For **Windows** user, please don't forget to add Python in your PATH as per below.
+1. Download the installer for the latest version from the [Python Software Foundation](https://www.python.org/downloads/release).
+2. Run the installer by double-clicking it, and following the succeeding instructions.
+
+!> For **Windows** users, please don't forget to add Python in your PATH as per below.
 
 ![Add Python to PATH](https://eavictor.files.wordpress.com/2016/05/add_python_3-5_to_pathinstall_now.png?w=594)
 
+
+!> For **OS X** users, ensure your Mac settings allow installing packages that are not from the App Store. Go to `"System Preferences" > "Security & Privacy," > "General"`. Set "Allow apps downloaded from:" to "Mac App Store and identified developers."
+
+
+### Linux
+
+Check the Linux distrubution using the `terminal`
+
+```
+grep ^NAME= /etc/os-release
+```
+
+Type one of the following commands in the `termimal` depending on your respective Linux distribution.
+
+* **Debian** or **Ubuntu**
+
+    ```
+    sudo apt install python3
+    ```
+
+* **Fedora**
+
+    ```
+    sudo dnf install python3
+    ```
+
+* **openSUSE**
+
+    ```
+    sudo zypper intall python3
+    ```
+
+You can also try [compiling from source](https://realpython.com/installing-python/#compiling-python-from-source) if you want the latest version or an alternative installation of Python.
+
+### Chromebook
+
+For Chromebook users, you'll need to connect to a cloud IDE provider. You can follow [these instructions](https://tutorial.djangogirls.org/en/chromebook_setup).  
+
+
+
+Finally, [check if you have successfully installed Python](#check-existing-python-installation).
+
+
 Done! You can now start coding in Python!
 
 ## Put your thinking cap on!