If you want to practice this contour, I recommend a good way is to stand upside down. Other methods can only increase some muscles, but handstand is comprehensive. Now practicing street dance means practicing handstands a lot, and then the outline of upper body muscles comes out. I used to be thin, too I'd better cooperate with push-ups and sit-ups, which will be very effective. If possible, you can also practice street dance, and then your muscles will definitely come out.