Step 1 : List down all your competitors
Step 2 : Go to Ahrefs.com
Step 3 : For every competitor. Find where they are getting their backlinks from and Export the data to an excel sheet.
Step 4: Go to each URL and see the Authors name and Domain and enter it in an excel sheet.
Step 5: Enter the details of the Authors and the Domain in an excel sheet
Step 6: Upload this to Find That Email – Bulk Find tool
Step 7: You will receive an email with a list of email addresses of all the authors of the articles that have mentioned your competitor.
Step 8 : Reach out to them and ask them to mention your product as well
Step 9 : Rinse, Repeat.
That was a short summary, if you want the exact step by step, visit this link