as someone who uses facial sheet masks all the time, I am not sure that is a good idea to reuse them like that.
If you really want to reuse them, I found this online
Here`s how to get 2-3 uses out of each mask:
1) Open your mask, remove the backing, and gently squeeze the excess serum into a zip lock bag. Make sure to leave enough on your mask for your first application! Some of the essence will run down your hands so pat your face with it before applying the mask.
2) Don`t forget to pour in the excess from the package.
If there`s a lot, you can divide this into two zip lock bags.
3) Apply the mask as usual. You`ll notice that there`s still plenty of essence to soak into your skin!
4) Once done, boil 1-2 cups of water.
5) Place the mask in pot and boil for one minute to sanitize.
6) Remove the mask with tongs or chopsticks.
7) Hold the mask under cold running water or place in a bowl of cold water to cool it off.
8) Gently squeeze all the water out of the mask.
9) Fold up the mask and place inside the zip lock bag filled with essence. Shake the bag around or squeeze the essence into the mask to let it absorb.
10) Store the baggie in a safe place or chill it in the refrigerator. When you`re ready to use it, remove from, bag, unfold, and apply like usual. As good as new!
12) Repeat the boiling process for the mask if you made up a second baggie of essence.
Also, if you don`t want to go through the boiling/sanitizing method for the mask, your can buy just the sheet masks in bulk for really cheap!
from
http://www.luuux.com/viz/how-to-reuse-your-face-sheet-masks-1
or you can squeeze out the excess essence into a little jar, put it in the frig and just use it as a serum without the mask
it is the bacteria that is lurking on the facial sheet mask - it could transfer onto your face (if you have acne or other skin conditions) that is worrisome about reusing it.
you can pick up facial sheet masks pretty cheaply. Walmart sells My Beauty Diary, which are amazing facial sheet masks - the red wine is fantastic.