I made my SeeU ears with craft foam
It's not the best way, but it was the fastest and cheapest thing I could think of (excuse crappy paint job please~)
It was trial and error for me to get the shape to something I was satisfied with. I did make a final pattern but unfortunately I don't have it so I can't share it with you D: It's not bad though. Just a tetrahedron but with curves instead of straight lines. Fiddling around a bit you'll figure out just how much of a curve you like.
The "speaker" part I just cut foam and shaped it into a cone, cut the end off the cone and put a circle there instead (if that made any sense whatsoever). If you want, you could make the outer rim raised, I couldn't cut circles out of foam that neatly so I chose not to. If you have flat ring type things convenient you could use that instead of trying to cut perfect little foam circles.
I used the gel super glue to attach everything together. After testing out different overlaps, I found that if I wanted the front face to curve in and the back edge to arch the way it does, this works best.
I used hair velcro to attach them to my head since I don't like headbands. They stuck for a whole afternoon of running, jumping, and ddr-ing. Of course, my wig fibers may be different from yours so I can't guarantee success.
Since I didn't make the official SeeU outfit (I did the wonderland version instead) I didn't have to make the cuffs, but I think they can also be made from foam...I started one cuff but I never really finishes them. I just messed around with cones until I found a shape I liked (last picture, bottom right). I think if you heat the foam and then cheesecloth the back so the shape stays, it should all work out~
Hope I provided an acceptable alternative~