I followed the steps from Michelle Phan's video.
And on my own accord added a few drops of lemon juice! According to my research many has said that you can almost add in anything you want. From yoghurt, to aloe vera, honey etc! For me I added lemon juice cus it's a great agent for skin whitening :)
Aloe Vera is a natural agent for reducing redness so to those who've got redness on your face I'm sure aloe vera works better since lemon juice is a little acidic and might aggravate the redness.
As for honey it's good for moisturizing so to those who're worried that aspirin might dry out your skin you can add in honey to neutralize the mask :)
Remember to moisturize after your mask as aspirin can be very drying to the skin! Also do take note not to leave it for too long.
P/S: aspirins are available at any pharmacies or medicall halls. (medical halls are way cheaper)
GOOD LUCK AND HAVE FUN!