Hi guys; here's my octopus costume!
To make, I sewed a belt out of the satin fabric, eight tentacles, and then put them all together. Here's the fabric pre-tentacle:
And the sewn tentacles:
Now the tentacles are attached to the belt, but not yet stuffed or closed:
I stuffed them with plastic bags (because I am a poor college student ) and added wire hanger backbones so I could adjust the legs however I liked.