Whats the best way to teach someone MTG these days? Im a veteran but never figured out how to get someone quickly up to speed from zero.

I have started people out concentrating on just casting and learning turn phases. We ignored any abilities of the cards, power, toughness and  casting costs. 
Depending on how fast they are picking it up I introduce more complexity.
Its been the most successful way to introduce new players.

I'm a skating instructor/ hockey coach, 3d printing geek and feline servant.

If they are struggling with the basics we can stay there, in the end they are at my table smiling and having fun. I'd rather have a new player enjoy their experience vs stress them out.