When and How Do I Introduce a New Person to My Toddler?

When and how do i introduce a new person to my toddler? It's a new friend slash someone i'm dating. I keep hearing a year, but i can't imagine continuing a relationship with someone that long if they haven't at least met my child. We always want to help our children make sense of things. There are appropriate boundaries. Don't just go with their advice or listen to them over in the short term.