Instagram does not allow you to post links as comments or with pictures.  You must post the link in your bio.

You can do this by following these instructions:

  1. Open your Instagram mobile app.
  2. Visit your profile by tapping the person icon on the bottom right.
  3. Tap "Edit Profile" at the top of the screen.
  4. Write a custom description in 150 characters or less.
  5. Add a brief link to your website in the form of