A really good, supporting, racer-back sports bra, a racer-back tank top (sometimes...sometimes it's just the sports bra), and short mesh shorts, usually. I also almost never wear shoes to workout at home. If I do wear shoes, it's my jazz sneakers because they are so lightweight and comfy
I like racer back tops and bras because I can see my back and shoulder muscles (or lack thereof, depending on where I am at in my fitness journey!), which is very motivating to me, because I like to develop those areas the most.