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.

yeah this layered approach seems like the way to go — still takes a long time tho

Every year we get more keywords, interactions and just more complexity. The layered approach will be best since you could spend several sessions just on the color blue and the stack, optimally tapping and waiting to cast. Magic is just complicated, a slow drip is the best way to teach someone

So true, I took about 7yrs off from MTG. When I came back I was in shock!