No music, quiet, just listening to anything and everything you can. it can be your own footsteps — focus on your pace if you want. If there are birds near where you live I’d highly recommend the Merlin Bird ID app for birdsong identification. It’s crazy what simply existing in the presence of another living thing can do, especially when that something isn’t human. if you live in a city, listen for people’s laughter or children’s voices. When I feel all consuming sadness it often helps for me to get moving (I like hiking but I live in a place that allows it) but it also helps to listen, and in doing so imagining that I am the same as everything else — the birds, the air, the ground. It takes the pressure off existing.