To use this login you first need to make sure that you've registered with LinkedIn Developer. Follow these steps for registering to the LinkedIn developer:
Go to LinkedIn Developer.
Log in to LinkedIn account.
Click Create Application.
Fill the form with the required details.
After filling the form, Click on your app's name and find Client ID and Client Secret under Authentication tab. You will need these credentials later to setup the LinkedIn provider in store.
Enter the URL of your website/store under Authorized Redirect URLs.
After you are done with the above details you now need to add the credentials you got in step 4 in your store's LinkedIn login provider.
To configure Linkedin login in StoreHippo,