First I started with the tail of the mermaid costume since that was all sewing. I literally fixed the skirt so it fit tight against my butt and sewed it so the raw edges faced outward as my “tail”.
Then I started on the top. I used a bathing suit top I didn’t wear anymore. I got netting from Micheal’s and cut it how I’d want it on my body then sewed pieces by hand onto my bathing suit top. I sewed the shells on after that and then hot glue gunned the little shells and starfish on the top.
Super easy and super cheap. I got the fabric 50% off and the shells and starfish came from Micheal’s for 2$ each. The netting was about 4$ for a big strip.