small pieces of felt in white and pink (or the jellyfishy colors of your choice)
a bit of stuffing
a five(ish) inch piece of ribbon for hanging
sewing machine or needle and thread (in pink and white)
printed templates (below)
Cut out paper templates; pin to felt and cut the number of shapes indicated by the template. (For the teardrop shapes, I traced the templates, since pinning such small bits is hard.)
Position the white teardrop pieces on the pink bell pieces and fasten with a whip stitch or running stitch if you're sewing your jellyfish by hand. Alternately, you can attach with your machine.
To create the tentacles, cut each felt circle (3) in a spiral beginning at the outside and working your way in to the center.
Position the top of each tentacle between the two lower-body pieces, so each aligns with one of the three lobes. Pin and sew the two lower-body pieces together, making sure to catch all three tentacles between them. (Again, you can use a whip stitch or running stitch or sew the pieces together on your machine.)
Insert the lower body at the center bottom between the two bell pieces and pin. Beginning near the top, sew the two bell pieces together, securing the lower body between them and leaving an opening (as marked on the template) at the top for stuffing.
As you sew closed the opening, catch the ends of the ribbon, folded in half, in your stitches, and voila!
I've made one jellyfish on my sewing machine and one by hand--the machine version is neater and quicker, but you can make the hand sewn version while you stream episodes of Felicity on Netflix, so it's a tough call.
(If you enlarge or shrink the pattern pieces, you can make these in many sizes--attach them to a wooden hoop and you'd have a lovely mobile. The pattern pieces could also easily be used to create jellyfish applique. Have fun!)