From DIA:
Take train to Union Station – Airport Terminal: follow signs for Westin hotel, when outside take the escalator down to the train platform. Hop on the A-Line ($9 one way, runs every 15-30 minutes). The A-Line drops you off at Union Station (train’s last stop).
Take Bus to Ember Hostel: Grab the number 0 at gate B20. You will get off at Broadway and 9th Ave. We are just two blocks east on 9th Ave. We are next to the parking lot.