Ever wanted to channel your inner old-Sheikah-lady-scientist-trapped-in-the-body-of-a-child? Fret no more, this file's got you covered! Just insert the tabs on the arms into the slots on the inside of the frame and glue them into place. I couldn't tell from screenshots if she's supposed to have fins on the sides, so accuracy freaks may want to add some craft foam fins if you find a nice piece of concept art that clarifies her appearance.
Purah and The Legend of Zelda: Breath of the Wild are property of Nintendo.
August 7, 2017 update: rounded out polygons of the circles and made minor tweaks to improve symmetry.
Just glue and paint!