At this link https://docs.google.com/forms/d/e/1FAIpQLSeqOTiHhH-vzs9lUcceZBX19kGdNnKf2kCqt1j23pU06oDQWg/viewform
you have just to put a mail / twitter account and follow and retweet their pinned message, then copy/paste the retweet link and after give your eth adress and say no if you don't wanna donate. Dat's all !
Have a nice day !