Ask HN: How do you prefer to differentiate people at a networking event?

I've been to some networking events where people have different colored dots on their name tags. Green for developer, yellow for designer, orange for founder, blue for marketing, etc. Do you personally get use out of this at networking events? Or is it too confusing to remember what all the colors mean? Have you seen any other effective ways at networking events of helping people connect with who they truly would like to connect with?