The steps below are taken directly from the OneDrive developer documentation. Please check the source site for the latest updates.

1. Go to the Live SDK app management site.
2. If prompted, sign in with your Microsoft account credentials.
3. If you are not immediately prompted to provide the app's display name and primary language, click Create application.
4. Type the app's display name and select the app's primary language.
5. Read the Live Connect terms of use and the Privacy and Cookies statement, and then click I accept. A client ID is created and displayed in App Settings. It should look something like this: 00000000603E0BFE.

1. In the Live SDK app management site, select your app and click Edit settings > API Settings.
2. Under Redirect URLs, type the redirect domain you will be redirecting users to
3. Click App Settings. On the application summary page, the client secret is displayed. It should look something like this: qXipuPomaauItsIsmwtKZ2YacGZtCyXD

Create your onedrive-config.json. It needs to contain:

{
  "client_id": "YOUR_ID",
  "client_secret": "YOUR_SECRET",
  "redirect_uri": "YOUR_REDIRECT_URI" // eg, http://dillinger.io/oauth/onedrive
}

Set the following environment variables if adding onedrive-config.json may present a challenge (when deploying on Heroku for example)

onedrive_client_id=YOUR_KEY
onedrive_client_secret=YOUR_SECRET
onedrive_redirect_uri=YOUR_REDIRECT_URI