update README

Author: sanfilip

README.md

@@ -1,16 +1,78 @@
 Paperspace API for Python
 =========================
 
-Sample usage:
+Sample usage
+============
+1. Make sure you have a Paperspace account set up. Go to http://paperspace.com
+   to register.
+
+2. Send an email message to support@paperspace.com to request access to the
+   Paperspace API Beta program.
+
+   Wait for an email confirmation indicating your account has been approved
+   before proceeding.
+
+3. Use pip or pipenv to install the paperspace-python package:
+
+    pip install paperspace
+
+4. Download your api key by executing the following:
+
+    python -m paperspace.login
+
+  Follow the prompts to enter your Paperspace email and password.
+
+  You can also enter your credentials directly on the command line as follows:
+
+    python -m paperspace.login <email> <password> [<api_token_name>]
+
+  Note: your api key is cached in ~/.paperspace/config.json
+  You can remove your cached api key by executing:
+
+    python -m paperspace.logout
+
+5. Execute the sample script hello.py:
+
+    python hello.py
+
+  The script will be run on the remote job cluster node, and its output will be
+  logged locally.
+
+
+A slightly more complex example
+===============================
+# tests/test_remote.py
+import os
+import paperspace
+
+paperspace.jobs.runas_job({'project': 'myproject', 'machineType': 'GPU+', 'container': 'Test-Container'})
+
+print(os.getcwd())
+print('something useful')
+
+
+Other examples
+==============
+See the scripts in the test folder for other examples.
+
+
+Other Authentication options
+============================
+1. Specify your apiKey explicitly on any of the paperspace.jobs methods, e.g.:
+
+    paperspace.jobs.create({'apiKey': '1qks1hKsU7e1k...', 'project': 'myproject', 'machineType': 'GPU+', 'container': 'Test-Container'})
+
+2. Set the package paperspace.config option in your python code:
 
-    import paperspace
+    paperspace.config.PAPERSPACE_API_KEY = '1qks1hKsU7e1k...'
 
-    paperspace.config.PAPERSPACE_API_KEY = '14a4bc1cbc414...'
 
-    paperspace.jobs.runas_job({'project': 'myproject', 'machineType': 'GPU+', 'container': 'Test-Container'})
+3. Set the PAPERSPACE_API_KEY environment variable:
 
-    print('hello paperspace!')
+    (on linux:) export PAPERSPACE_API_KEY=1qks1hKsU7e1k...
 
+  Note: the above methods take precedence over use of the cached api key in
+   ~/.paperspace/config.json
 
 Contributing
 ============