Print the the holographic vinyl template from the SVG file provided by the link above. Once it has printed, verify that it is the correct size by checking the 1" reference square against a ruler.
Next, cut away the extra paper around the printed pieces, leaving a small margin around the outlines of the two pieces. Unroll and smooth out the holographic vinyl, then place the template on top with the printed side facing the vinyl. Using tape (painter's tape is fine), secure the template to the vinyl by placing tape around all the edges as shown.
Turn the vinyl and template over. You will be able to see the outlines of the two pieces through the translucent vinyl. Using sharp scissors, cut around the two piece outlines, starting at the middle of the template and cutting the taped edges last.
If you have a laser cutter or vinyl cutter that can handle 2mm thick EVA foam, you can import the vector template for the EVA foam pieces directly into your software and cut them using your machine. You will need to cut an additional rectangular piece that is 12" long by 36mm high. If you don't have a machine to cut these pieces, it is straightforward to cut out the pieces by hand using the method described below.
Print the template for the EVA foam from the SVG file provided, and check the scale using the 1" reference square included on the page. This template contains outlines of every foam piece except the largest one, which is too long to fit on printer paper.
The largest foam piece is a rectangle 12" long by 36mm wide. While the template doesn't have an outline of this piece, it does contain two lines separated by exactly 36 mm which you can use to draw cutting lines directly on the foam. Flip the EVA foam over so the paper backing faces upwards, and, using the markings on the template, create a series of marks spaced 36mm from the edge of the foam sheet. The EVA foam sheet shown here is exactly 12" long, so it was straightforward to line up a ruler with the marks and cut along the edge of the ruler with a craft knife. Alternatively, you can draw a straight line joining the markers with a pen and ruler, then use scissors to cut out the rectangle.
Once the large EVA foam piece is cut, trim the template around the group of remaining pieces. Using a glue stick or double-sided craft tape, stick the template to the paper on the back of the foam. You can then cut along the printed outlines with scissors or a craft knife to create the rest of the foam shapes.
The small notches in the edge of narrowest foam pieces can be tricky to follow with a regular scissors. To cut the notched piece accurately, It's easiest to cut a straight line directly along the notched edge first, ignoring the notches, and then go back to cut them out afterwards. The small details are most easily created using a craft knife aligned with a ruler or a small, sharp scissors, such as embroidery scissors.
When finished, you should have all the pieces shown in the final image.
The components of the collar fit together in curved layers. The different materials in the build have varying degrees of flexibility and stretch. In order to prevent the collar from wrinkling or pulling when worn, it must be constructed with the correct curvature.
You'll need to find an appropriately sized "model" of your neck to build it around. Measure the circumference of your neck using a piece of string or cloth measuring tape, and search your surroundings for a sturdy cylindrical object with a similar circumference. The closer you can get to your actual neck size, the better. I found a 28-oz can of tomatoes that was within 1/2 inch of my neck's circumference, and removed the label to make it easier to work with.