[doc] Describe the pull/fork/modify/push work flow

doc/quick_start_guide.rst

@@ -60,7 +60,10 @@ either a reduced or different dataset.  Once you have everything working as
 expected, push the resulting code to the platform and execute it there, for
 validation.
 
-1. Get (or pull) the experience you would like to work on:
+The following steps describe the procedure to start from an existing
+experiment and build on that.
+
+#. Get (or pull) the reference experience you would like to base your work on:
 
    .. code-block:: sh
 
@@ -74,7 +77,32 @@ validation.
       Values within angle brackets (``<`` and ``>``) will depend on the asset
       name.  Replace these values by appropriate actual values.
 
-2. Edit the code:
+#. Create your own fork from the experiment:
+
+    .. code-block:: sh
+
+        (beat) $ beat experiment fork <experiment-author>/<experiments>/<toolchain-author>/<toolchain-name>/<toolchain-version>/<experiment> <your-beat-user-id>/<experiments>/<toolchain-author>/<toolchain-name>/<toolchain-version>/<experiment-name>
+
+#. Create your own fork from an algorithm you want to modify:
+
+    .. code-block:: sh
+
+        (beat) $ beat algorithm fork <author>/<algorithm>/<version> <your-beat-user-id>/<algorithm>/<version>
+
+
+    This will allow you to use your own modified algorithm for your fork.
+
+    .. note::
+
+        You will have to update your experiment fork in order to use your own
+        algorithm(s).
+
+    .. note::
+
+        You do not need to fork an algorithm, you can use a different one as
+        long as its inputs and outputs matches the one you want to replace.
+
+#. Edit the code:
 
    .. code-block:: sh
 
@@ -83,7 +111,7 @@ validation.
    This will open your default configured editor to edit the code of the
    algorithm passed in parameter.
 
-3. To edit any other asset, just start the editor, optionally pointing to the
+#. To edit any other asset, just start the editor, optionally pointing to the
    prefix of interest:
 
    .. code-block:: sh
@@ -95,13 +123,13 @@ validation.
    also allows to start your favorite editor for code or documentation
    modification.
 
-4. Once the editing is done, you can run an experiment like this:
+#. Once the editing is done, you can run an experiment like this:
 
    .. code-block:: sh
 
       $ beat exp run <experiment-author>/experiments/<toolchain-author>/<toolchain-name>/<toolchain-version>/<experiment-name>
 
-5. Once the experiment runs successfully on your machine, you can upload it to
+#. Once the experiment runs successfully on your machine, you can upload it to
    the online platform and run it there.
 
     .. code-block:: sh