I found a little bit of fabric at JoAnns and bought it, planning to make a mermaid blanket for my daughter. She saw the fabric and begged for a mermaid tail. There are many tutorials online for how to make them so I looked around and combined the ideas I saw. The total cost of this tail was $8.
It would be best to buy a fin but I didn't want to spend the money on one without knowing if she could swim with one, so I decided to make my own. To make one, you'll need a firm plastic (I used a sterlite storage tub), stretchy fabric, elastic, and velcro.
First, I printed some mermaid tail fins and found one I liked. I traced it on the tub and cut it with a jigsaw. I then sanded the edges.
I had my daughter stand on the edge and traced where her feet would be. The rectangle is where I wanted to add the foot strap.
I sewed the fabric to cover her feet and made it twice as long as the rectangle on the front. I added strap to the back with elastic inside to keep it around her ankle.
I drilled holes in the corners of the rectangle to keep the plastic from splitting, and then cut along the lines so I could insert the fabric foot strap. I sewed velcro on the ends of the foot strap so that it could be adjusted and removed if needed. Then I wove it through the slits and tried it on myself.
I think it would be better to make the part by the feet more narrow so it's easier to flip in the water.
At this point, I followed the other patterns I found. I traced my daughter's body from the belly button down to her toes and traced the fin as well.
I didn't have enough fabric to do one solid piece all the way down so I cut the fun pieces separately and sewed them on.
After both sides are cut and sewn, pin them together and sew all but the end of the fin. Leave that open so you can slip the fin in. I cut mine to the shape of the fin on the bottom and that made it rather loose once it was in the water. I've seen a lot of tutorials where they leave the bottom straight and that works a lot better. I ended up adding a zipper to this one later on.
After you sew it, slip the fin in and allow your little mermaid to try it on! I ended up having to cut some excess off of the foot strap to make it tighter but she was able to swim in it pretty well.