I like to pile my coat and tote bag and purse all in a big heap on my lap. That way, if I see a cute guy, I can quickly dump all my shit everywhere and act all flustered so maybe he'll come help me.
And then we both try to pick up the same book at the same time, our hands brush against one another, we lock eyes, he instantly proposes, I say yes, everyone claps...
Honestly, watch out for people who don't put their stuff in the seat next to them. It might be a trap.
My bag goes in the floor in front of me, between my legs, or in my lap if there's no room. The only time I put it on the seat next to me is if the bus is almost empty, there's no worry that I'm keeping anyone who needs a seat from sitting.
I'll only move my stuff on my lap if all rows/pairs of seats have at least one person on them. Sitting next to a stranger when there are plenty of empty seats with no one next to them is super weird anyway.