Here's what I do for tips

1. Keep the car clean.
2. Smile and say hello to the pax.
3. Confirm the drop-off address.
4. Tell them how long the trip will take and give the precise ETA.
5. Play jazz on Spotify.
6. Try to start a convo by saying "How are you today?" or homeschooling. If they say nothing after "I'm good," I keep my mouth shut and drive. If they keep the convo going, I join in (I'm shy though, so that can be difficult).

On a good day, half my pax (usually around 20 per day) will tip something.

Anyone have any other ideas?