This is my lab mask. The "point" goes down, chinwards. The only trouble I've had is finding the right shade of pink vinyl, and I recommend something with a small amount of 2-way stretch. I also recommend making a test pattern to figure out the size you need - either with scrap fabric, felt, or even paper. In fact, if you're less concerned about accuracy, felt makes a pretty good substitute - it's easy to breathe through, the edges don't fray, and easier to find than pink vinyl.
