I would buy a plain, plastic white mask (like this, you can buy one at Michael’s craft store). Also get a lot of newspaper and some Elmer’s Art Paste (simply mix with cold water and it becomes a kind of gel you can put your hands in and essentially paper-mache/mod-podge newspaper to stuff with).
Layer, layer, layer the newspaper to kind of even out the mask’s surface-- the mask’s shape is much less a proportionate human face than a kind of silly flat simplification of one). You can layer newspaper over the eye-holes, you’ll be re-making them later anyway.(In addition to its actual reference like HERE and HERE, it reminds me very much of the plastic kids’ masks of popular anime characters you kind at Japanese festivals, like THIS or THIS, so that’s the kind of look I imagine the Sparkling Justice mask would be like.)You can add the ears and hair-wings with like, cardboard, and shape those in art-pasted newspaper too.Once the art paste is dry (probably by the next day) you can hot-glue on a layer for the hair bangs and then another layer for her ‘crown.’ Also poke 2 holes where the white circle in the center of the eyes should be.At this point, you can start painting. Put down a layer of gesso/white acrylic paint, and once it’s dry, sketch where the details go-- the hair lines, eyes, crown details, mouth, etc. Then paint it with acrylic paint.Once it’s dry, get some white mesh fabric (think like...as close as lace mesh, not like a net. You should be able to see through it when it’s right in front of your eyes, but seem opaque from a few feet away) and cover the eye-holes from the inside of the mask. Just hot-glue it up in there.And as a finishing touch (make sure your paint is 100% dry!!!), use high-gloss varnish (or Elmer’s glue actually works too, since it dries clear) and cover the mask in it-- it’ll dry clear and give the whole thing a plastic-y shine.
It shouldn’t be too heavy, considering it’s made mainly of paper product. You can attach an elastic band around the back to wear it. As an alternative that’s probably slightly more money but slightly less work, you can buy one of those plastic kids’ Japanese festival masks and re-paint it into a Sparkling Justice mask, perhaps.
