You can connect your Facebook account after you create an account with your email address from the 'Edit Your Profile' page.
Once you are there, click the Facebook icon near the bottom right of your cover photo to access social network linking options. Please be aware that once you connect your account with Facebook, it cannot be disconnected. Other social media sites can be disconnected.
You can also connect your Wantedly account with the following sites.
If you are still having trouble, contact the Wantedly Customer Relations Team from here!