Excited to post my first ever instructable! Hope you enjoy my take on Hedwig. Let me know if you have any questions. I would be more than happy to help.

Step 1: Sketch Costume Design

Step 2: Gather Supplies

Supplies Needed for Hedwig from Harry Potter Costume (not all supplies are in image please read below):

1 White sweater. (I purchased mine for $8 from Amazon)
Black Leggings or pants
3 yards of white flannel (I used every scrap. if you want more feathers I would suggest getting more)
Fabric Scissors
Paper Scissors
paper
glue gun (if you don't want to sew a glue gun can be used for the whole project)
felt in orange(beak of owl mask), white(owl mask), brown (Hedwig's feet)
ribbon
Needle and Thread (optional)
sewing machine (optional)
cutting board (optional)
rotary cutter (optional)

Step 3: Cut Out Fabric Wings

Lay the Fabric on the ground
Place Sweater on top of fabric
Cute the fabric so that it reaches from one wrist of the sweater to the other.
1. Save left over fabric for feathers
If you want your wings to be symmetrical fold the fabric in half. Place in the center of the sweater and cut a curve that looks best to you. I cut a few times before settling on a design I liked.
unfold fabric and place sweater on top. Make sure you like the look. if it is a little too short you can add longer feathers to make it look more full.

Step 4: Create Template and Cut Feathers

Create a template for you feathers. I drew a one shape then traced is over and over in a line to create a larger template to work with. I left the top connecting the individual feathers to make sewing or hot glueing the pieces easier.
Cute out strips of fabric that are a little bit taller than your template. (my template was about 4.5 inches so I cut my fabric is 5 inch tall and total length of the fabric)
Trace template with pen onto fabric and cut out. No need to be a perfectionist. The feathers will all blend together and look great.

Step 5: Lay Out Feathers and Sew From Bottom Up

Lay out all your feathers before sewing or glueing to make sure you have the look you want.
Work from the bottom up. Sew or glue your pieces to the base fabric.
I tried to alternate the points when lining up new fabric strips to give it a more organic look.

Step 6: Attach "Wings" to Sweater

Flip over the finished wings and place the sweater on top
Hot glue to the back of sweater or stitch with needle and thread every 3-4 inches along the top of sweater to tack the wings to the back of the sweater.

Step 7: Make Hedwig Felt Owl Mask

Sketch out an owl mask template on paper.
1. identify the distance between your eye and mark on paper
Trace mask template on felt and cut out. (you may need to make som alterations depending on eye and nose placement)
Cut scraps in strips with notches to go around the eyes of mask
cut out a tear drop shape for Hedwig's beak.
Hot glue eye fringe, head fluff, and beak to mask.
Sew or glue ribbon to sides of mask. Cut to the dimensions of your head. Make sure you have enough to tie a ribbon in back.