Good question. And one that my team and I have devoted the last year or so to answering. In the end it turns out to be remarkably simple. Language describes human situations. On the internet, there are cat pictures for every possible human situation. So all you have to do is to design a course which introduces the phrases that you need to learn, and pairs them with cat pictures that represent them. Science has repeatedly shown that imagination, cuteness and humour each has the capacity to significantly boost cognition. So the cuter and funnier the pictures, the better you'll learn.