Update build instructions

guides/contrib.rst

@@ -11,18 +11,24 @@ simple steps provided below.
 
 .. note:: `OpenBeagle <https://openbeagle.org/>`_ is a self hosted instance of open source program called `GitLab <https://about.gitlab.com/>`_.
 
-.. tip:: If you want to build on your local machine we have added ``venv-build-env.sh`` and ``requirements.txt`` 
+.. tip:: 
+    If you want to build on your local machine we have added ``venv-build-env.sh`` and ``requirements.txt`` 
     to help you setup sphinx and all the other dependencies. Execute these commands in your terminal,
+    
+    Install python modules and setup virtual environment,
 
     .. code:: shell
 
-        chmod +x venv-build-env.sh
+        . ./venv-build-env.sh
+
+    Build and serve it live using ``sphinx-autobuild``,
 
     .. code:: shell
 
         make livehtml
 
-    Now, you can open `http://127.0.0.1:8000 <http://127.0.0.1:8000>`_ on any browser to see the rendered HTML with live updates.
+    Now, you can open `http://127.0.0.1:8000 <http://127.0.0.1:8000>`_ on any browser to see the rendered HTML with live updates. 
+    Clear cookies and site data in your browser window to view up to date site.
 
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