Step One: Find a pair of modern 3D glasses.
Step Two: Go Here and print out the eye templates.
Step Four: Put the cut outs on top of the frames. The plastic should rim should secure them, though you can use a glue stick if you'd like.
Bonus! If you'd like you can use an X-Acto knife to cut out the shape, you'll still be able to see through them! Then you can bring them to the theater and be the coolest guy or gal seeing Happy Feet Two.