Advice on getting players to settle down before a session?

Usually we all sit around the table, waiting for people to slowly filter in, having idle conversation and stuff. Eventually everyone arrives and things continue for a while but I'm getting anxious to get started, knowing we have limited hours to play in and wanting to get through the session. But I don't know how to get everyone to transition into the session and begin to focus on me without being rude and saying "Everyone shut up. D&D is starting now"

The only advice I've heard for this is to stop talking and wait for the players to notice and stop talking themselves, but that's never worked for me so I don't really know what I should be doing.