Last Christmas my son got "Sonic Colors" for a gift. Soon we had a kid running around the house at top speed claiming to be as fast as the blue hedgehog. This enthusiasm for speed continued for months and as a result I asked him if he would like to be Sonic for Halloween. With an enthusiastic "yes" I began the planning process.

Materials Needed:
- Cereal Box Cardboard
- Masking Tape
- Blue Fleece
- Blue long sleeve shirt and pants
- Fabric adhesive
- Hot Glue Gun & sticks
- EVA foam (1/2")
- Craft Foam
- Elastic Strips
- Red, White & Gold spray paint
- Face Paints
- White Gloves

Step 1: Planning

I started by trying to get the right proportions. Sonic has a really big head and feet, so I looked up some pictures online. Then I measures my son's height and made some rough measurements to estimate how big the Sonic "helmet" would need to be. I printed a picture of his head and sketched over it to plan out how it would need to look. This helped in the construction process.

Step 2: Basic Head Shape

I started by cutting strips out of cereal boxes (the long way). First, measure the distance around the head. Make the head band be a little larger than this as you don't want it too snug that it is hard to get on. Then, make 2 bands that cross the head. I measured these while on hi head to make sure they were the right size. Use masking tape to fix them together.
Then I made another strip to go along the back of the head and taped it up to the head band. This will help the helmet to be more stable an not wiggle around when he moves.
Now you have the basic foundation to build the rest on. I also added the shape for the eyes. I had my son put it on several times to get the placement and size right

Step 3: Building Up the Head

This is where it started to get a little trickier. Obviously my son's head is not as big a Sonic's. I had to then build over the basic foundation making the helmet larger. I started with the center piece and checking the height proportion on my drawing. I added a support piece on the middle of the head to keep it up.
Next add more cross pieces checking shape and size. Place support pieces to keep it from collapsing. From there, keep adding pieces to connect it all together. On the next step, I cover it all with masking tape, and the more cardboard there is the sturdier and round it will be.
I had my son try it on multiple time to make sure it fit and the shape was right.

Step 4: Add Tape and Ears

Once the shape is right start covering the whole thing with masking tape. I covered it bit by bit connecting the cardboard strips. Make sure to do the outside and inside since the sticky side of tape does not mix well with hair.
After it is covered, add the ears. I drew on the position of the ears right on the tape. Then I used cardboard to make ears. Again, measure the right size. I cut the front piece first for this. Then I measured the side pieces to custom fit the shape of the helmet. Tape it together and to the helmet.

Step 5: Cover With Fleece and Add Spikes

This step is a bit more challenging. I enlisted the help of my wife for this as my sewing skills are not great and I needed more than two hands for the gluing process. I couldn't have done all this without her.
I don't have any pictures of the process, sorry. Basically, we draped the fleece over the top of the helmet. Then we cut holes for where the ears were. Make small slits for this as the fleece is pretty stretchy. Then once we had it well positioned we sprayed on the fabric adhesive. Then, hot glue the edges to the underside of the helmet. Then cover up the ears with the same process.
Now for making the spikes. This is a basic cone shape sewed together. However, because Sonic's spikes don't stick straight up they have to be curved a bit. We tested this with paper first to get a template before cutting the fleece. Once formed, stuff them with batting (we used an old pillow). Then hot glue the spikes in place. Start at the top and work your way down making sure to stretch the fleece tight. Do this for all the spikes. The front spikes are bigger than the back spikes.
It's not in these pictures, but we also glued pink fabric triangles for the inside of the ears.

Step 6: Shoes

Not many pictures for this process. I free handed this whole thing. I started by trying to figure out the shape to fit neatly over my son's shoes. Once I got the paper stencils made I drew them on to the EVA foam. I cut those out and then heat formed them into place. To do that I put each piece in the oven (250 F) for 1-3 min. until malleable. Then I held the shape in place until it cooled.
Then I also cut out the buckles from the EVA. From the craft foam came the white stripe. I spray painted them all their respective colors.
I glued all the pieces together using hot glue. I also included elastic straps to help keep it on to my son's shoes.

Step 7: Pants and Shirt

Not many pictures for this either. Basically this was a similar process to the helmet with the spikes. There are two spikes on the shirt and a tail on the pants. However, we were able to sew these on.
Then we (my wife) sewed on the big flesh colored oval to the shirt. It looked great.

Step 8: Put It on and Look Awesome!

My son was super excited to try it on. We painted his face white for the eyes and his nose black. It all worked pretty well. We added a chin strap to the helmet to keep it more secure.
Unfortunately, the design of the shoes slowed him up a bit, but at least he looked super awesome!

Introduction: Sonic Costume