My daughter wanted to be Hello Kitty this year, and so she was. The costume is of felt for the most part. The arms (felt) were cut and sewn into an extra larger shirt to make it one piece that she could wear as a shirt. On the inside of the hands/mittens, there is a slit so she could take her hands in and out.
The jumper is also made of felt with adjustable straps. The bottom of the jumper was basted to make it look fuller and so that the length could be adjusted if need be. The legs/pants are made of felt with an elastic waist. I made them long so they would fit over her boots like feet.
I drew Hello Kitty’s face onto thin cardboard (template) and traced it onto the felt (2 pieces). After sewing the edges of the head and stuffing it with poly fill, it was too heavy for her to wear. I cut out another Hello Kitty piece of cardboard and stapled the two together as a frame. I slid that into the felt head and used styrofoam blocks and light weight paper to expand the head instead.
The eyes and nose are made out of sticky felt. The inside of the nose is a flexible screen so she could see. The head is attached with 2 velcro straps (1 on each side) that wrapped around her arms to hold it in place. The Hello Kitty costume took about 10 hours to make and I ended up using approx. 4 yards of felt. Everything was sewn inside out so that the seems wouldn’t be seen. This was actually a lot of fun and all the kids loved her.