I set out to make my own using household materials.
Supplies I ended up using:
X-acto knife(scissors are fine)
Step 1: Fit Foil to Face
After you have your foil, place is against your face. You should try to make sure the mask is especially defined around your nose. Once you're happy with the fit, draw on the opposite side where your eyes (and nostrils/mouth for full face mask) are. Don't worry about any accidental marks.
Step 2: Cut Out Features
I cut the eye holes particularly small as I'll enlarge them later.
Step 3: Tape It.
I use clear tape, although packing and duct tape would work. Tape the entire front and back of the mask. This makes the shape sturdier and prevents the aluminum from irritating the skin.
At this point, if you were going as a character like the tin man or something, you could stop.
Step 4: Paper Mache It.
A very small amount is needed here. Standard two parts water to one part flour recipe.
To make it dry faster, I tried a blow dryer but that ended up blowing some of the paper off. Instead, I put it in the oven set to broil on low. Be very careful to watch it and do not put this in the microwave! Turn off the oven as soon as the top looks dry and let it sit on the pan in the oven til the rest is dry as well.
Step 5: Finish It.
What I did here was first paint it white. Then I snipped off extra foil around the eyes and outer corners of the mask. An additional coat of black and then I cut the mask so it had triangle corners.
I will probably also end up gluing feathers to this mask for a black swan style look.
Step 6: Further Considerations
If it's for wearing, decide how you want to wear it. You can glue a stick (painted pain stirrers work well for this) to the mask or punch a hole/staple ribbon or a rubber band to both sides. If stapling, make sure your mask is sturdy or it will rip the staple when you try to put it on.
You may also want to add features to the mask--such as exaggerating the nose. This is very easy to do using paper mache pulp or clay. Overall, this is an easy project that can take less than an hour.