I designed this project as one session of a kids costume workshop series. I made a Bat-symbol to go with my sample cape, but the kids did a variety of designs that they drew or pulled from the internet. The possibilities are endless!

You can make a belt with matching fabric and some pouches to make it a utility belt, or you can just make the light up belt buckle, which this Instructable covers, and use a belt you already have!

See the other Instructables from the workshop here:

Light-up Superhero Cape

Light-up Wrist Bracers

Step 1: Gather Materials and Equipment

Materials:

Fabric Color 1
Fabric Color 2
Felt, a piece big enough to fit your logo on
Fuse-Bond, a piece bigger than your logo
Fusible Interfacing, a piece bigger than your logo
Paper print out or drawing of the logo you want to use (may need two or three copies depending on the design)
Glue Stick
Lilypad LEDs (they come in a variety of colors)
Lilypad Coin cell battery holder
Lilypad Twinkle
Conductive Thread

Equipment:

Hot glue gun
Large Eye Sewing Needle
Alligator Clip hook-up wires

Step 2: Make Symbol

For the symbol, you will be cutting and assembling layers of fabric using fuse-bond and fusible interfacing. The process will vary a bit depending on how complex your symbol is.

For the "Bat Symbol" this is the process:

Iron on Fusible Interfacing to the back of a piece of base (gold/yellow) fabric that is bigger than the outline of the symbol. This will add some stiffness to the fabric and keep it looking sharp.
Lightly tack the paper print out of the symbol to the back of base fabric making sure to only place glue outside of the symbol on the paper.
Cut out the base shape from the base fabric, and save the paper piece.
Iron fuse bond to the back of a piece of the second fabric (black) that is bigger than the logo part of your symbol.
Leave paper on fuse-bond and use glue stick to glue the paper symbol to the fuse-bond paper. If you have a an intricate design, make sure to glue it really well and let dry before cutting.
Cut the logo out of second fabric and peel off both layers of paper.Carefully place the logo on the background and iron in place

Step 3: Make Circuit Pad

The circuitry is pretty simple here, but it is essential that the "wires," which are conductive thread here, don't cross each other and short out the circuit. Because the spacing is pretty tight here, I just tied knots on all contact points with the conductive threads, and then glued them in place instead of actually sewing through the felt pad.

Poke five holes in the paper print out of your logo where you want the lights to show through
Transfer the dots onto a piece of felt cut out to be slightly smaller than the fabric logo
Tack LEDs in place with hot glue
Attach all negative sides of LEDs with conductive thread
Attach all positive sides of LEDs with conductive thread
Test connection with alligator clips and decide which blink pattern you like if you are using a Twinkle Board
Attach positive and negative threads from LEDs to the appropriate terminals on battery holder and Twinkle

Step 4: Assemble and Enjoy!

Check the alignment of the LEDs by turning them on and placing the symbol over the circuit pad. If the lights show through adequately just glue the symbol to the pad and string it on a belt. I

If the LEDs are too dim because of dark or thicker fabric, poke some holes in the symbol to let more light show through.

Hope you come up with some creative ideas. I would love to see if you do! :)