Early I posted the Design That Matters Face Shield - based off of the Prusa design - as materials are in short supply at local stores, I looked around the house for some mock up materials. A three hole punch Avery sheet fit perfectly - but materials specified on their website would are necessary. You need a very large rubber band to hold the mask together in the back. Large elastics are sold out in local stores. Ironically, to test it out, I had two gold elastics strips wrapped around a bottle of olive oil - worked! But not sanitary.  
Drawback - longer to print. More filament. Positives: more protective against patient spray.  

As another night comes to a close, still looking at faster options. Be safe. Be well.