Improve installation documentation.

docs/overview.rst

@@ -27,10 +27,20 @@ If you get an error, remove the word 'php' in front of the line. This depends on
 
 .. code-block:: bash
 
-    php composer create-project clastic/standard-edition path/to/install -s dev
+    $ composer create-project clastic/standard-edition path/to/install -s dev
+
+.. note::
+
+    If the installation fails, check if the ``composer`` executable works. You might need to
+    use ``php composer.phar create-project path/to/install -s dev`` if you installed composer locally.
 
 During the installation you will be asked to fill in some parameters. Make sure all the values are correct.
 
+You should now have a project located in ``path/to/install``. Please go to this folder and continue.
+
+.. code-block:: bash
+
+    $ cd path/to/install
 
 Clastic needs multiple assets to be installed in the correct place. The standard project contains a `Makefile`
 to simplify this process.
@@ -39,6 +49,13 @@ to simplify this process.
 
     make install
 
+.. note::
+
+    Now is a good time to have a first commit!
+
+Development
+-----------
+
 You can now start your developement environment.
 
 .. code-block:: bash