I’ve seen it done a few times now and I had to try it for myself: wearing a shirt as a dress. It took me a few try and a few different shirts but I finally found the right one. This is a men’s medium dress shirt that i’ve been holding onto because I really liked the print.
I basically just wrapped the sleeves around my chest and made a bow. I paired it with a tank because it doesn’t stay up as much as I’d like to, and also the vest to hide any extra bunching happening in the back (i.e folded over collar). The belt just makes it look more like a dress but isn’t really necessary.