I’ve gone through the quick-start for using Auth0-php, and it’s working fine. I would however like to provide a link to the user so that he can go directly to “signup” and not to login. Is there a signup() equivalent to $auth0->login()?

Yes, I appears that I can send it in as a parameter to the login() function in Auth0.php This is working: $auth0->login(null, null, array( "screen_hint" => "signup" ));