First add our chrome extension to your browser: here
Step 2:
Open the extension and click sign in.
Step 3:
Using the same browser, same chrome profile and then go to linkedin.com and sign in to your LinkedIn account.
NOTE!
To avoid detection ensure you don't use a different chrome profile as usual, don't login on multiple locations and avoid using LinkedIn when NoRecruit is working. You can use NoRecruit to reply to any incoming messages.