how to make a shark costume

My son loves dressing up. Whether it’s as a superhero, a tiger or a pirate he loves to make believe he’s a new person or creature. This shark shirt is easy to make and will provide hours of dress up fun. It also make a great Halloween costume or conversation piece when out and about!

Project estimate:

  • 2 grey t-shirts, $2 and up
  • Double-sided extra firm iron-on interfacing, $1 and up
  • Sewing machine or needle and thread, on hand
  • Permanent marker, on hand
  • Paper, on hand
  • Iron and press cloth, on hand
  • Scrap cardboard, free

Total: $3 and up

shark costume supplies

Step 1: Prep fabric

Before beginning, be sure to wash and dry both shirts to remove any sizing and prevent shrinkage later on.

Step 2: Cut out

Use a marker and a piece of paper to outline an image of a shark fin. Adjust size of fin based on size of wearer. Draw a dotted line around the silhouette, .25 inches from the edge. This will provide a seam allowance. See image as a guide.

shark fin template

Cut out interfacing the size and shape of the solid outline. Turn one t-shirt inside out and cut out two pieces of T-shirt from fabric, following the dotted lines (Pro tip: Make smoother seams by lining up the bottom of the shirt with the bottom of the cut out.)

trace shark fin

Step 3: Assemble

Leaving the pieces right sides together, use sewing machine to stitch with a medium length straight stitch around the sides of the t-shirt fabric, leaving the bottom open. Turn right side out and press.

sew fin with a 1/4 inch allowance

Insert the interfacing all the way into the fin pocket, trimming if needed to fit. Follow instructions that came with your interfacing to fuse it to the fabric.

insert interfacing into fin

Step 4: Attach

Fold bottom edge of fin fabric in to the center bottom of fin. Pin to hold fold if desired.

how to pin fin under

Fold t-shirt in half and press to great a press line going down the midline of the shirt. Insert scrap cardboard such as an old cereal box into the shirt.

press a crease into a shirt

Line the fin up with the crease you created on the back of the shirt, splaying the bottom edges of the fin out to either side. Pin fin edges to the t-shirt. Remove cardboard from shirt. Fold fin to one side and stitch the fin edge to the t-shirt using a narrow zig zag stitch. Repeat on other side of fin.

stitch shark fin

Step 5: Add Gills

Use permanent marker to draw two U-shaped gills on the side of the shirt under each sleeve.

draw shark gills

Have fun with your little shark!

toddler shark costume


toddler shark shirt

More shark crafts:
Follow Mrs. Greene’s board Shark Week! on Pinterest.