Start with the basics
Explain the objective before describing exceptions. Show the deck and any special cards, then demonstrate a complete turn with open hands.
Put it into practice
Teach the common decisions first. Give players a short reference for turn order and how a round finishes. Introduce unusual situations when they arise instead of overwhelming the group at the start.
Before your next session
Allow questions and a practice round. Keep the pace comfortable and offer a simpler game if the group prefers it. A successful introduction leaves people wanting another friendly round.