A pleasant smile is often the best introduction. That has also proved true when brothers and sisters engage in public witnessing using a literature cart.
بَلْ يَتَوَتَّرُ مُعْظَمُ أَصْحَابِ ٱلْبُيُوتِ إِذَا رَأَوْا غَرِيبًا عِنْدَ بَابِهِمْ .‏