Docs revamp. Part 2

docs/source/intro/setup.rst

@@ -0,0 +1,61 @@
+Project Setup
+=============
+
+We have just `installed Pyrogram`_. In this page we'll discuss what you need to do in order to set up a project with
+the library. Let's see how it's done.
+
+API Keys
+--------
+
+The very first step requires you to obtain a valid Telegram API key (API id/hash pair):
+
+#. Visit https://my.telegram.org/apps and log in with your Telegram Account.
+#. Fill out the form to register a new Telegram application.
+#. Done! The API key consists of two parts: **api_id** and **api_hash**.
+
+.. important::
+
+     The API key is personal and must be kept secret.
+
+.. note::
+
+    The API key is unique for each user, but defines a token for a Telegram *application* you are going to build. This
+    means that you are able to authorize multiple users (and bots too) to access the Telegram database through the
+    MTProto API by a single API key.
+
+Configuration
+-------------
+
+Having the API key from the `previous step <#api-keys>`_  in handy, we can now begin to configure a Pyrogram project.
+There are two ways to do so, and you can choose what fits better for you:
+
+-   First option (recommended): create a new ``config.ini`` file at the root of your working directory, copy-paste the
+    following and replace the **api_id** and **api_hash** values with your own. This is the preferred method because
+    allows you to keep your credentials out of your code without having to deal with how to load them:
+
+    .. code-block:: ini
+
+        [pyrogram]
+        api_id = 12345
+        api_hash = 0123456789abcdef0123456789abcdef
+
+-   Alternatively, you can pass your API key to Pyrogram by simply using the *api_id* and *api_hash* parameters of the
+    Client class. This way you can have full control on how to store and load your credentials (e.g.:, you can load the
+    credentials from the environment variables and directly pass the values into Pyrogram):
+
+    .. code-block:: python
+
+        from pyrogram import Client
+
+        app = Client(
+            "my_account",
+            api_id=12345,
+            api_hash="0123456789abcdef0123456789abcdef"
+        )
+
+.. note::
+
+    To keep code snippets clean and concise, from now on it is assumed you are making use of the ``config.ini`` file,
+    thus, the *api_id* and *api_hash* parameters usage won't be shown anymore.
+
+.. _installed Pyrogram: install.html