Hello! If I'm not mistaking there is tutorial for developers about how to do it. I did it yesterday and should wait till tomorrow. But you should keep your EOS ethier at MEW or Exodus. If you do - try to watch this video :
https://www.youtube.com/watch?v=d7tMZbNhwY8I've seen this video but I can't understand were can I find this 12 words??