I haven't printed it out yet (it's about 18th on my to-do list...) but it looks sound, I'm pretty sure the facial size should fit most heads but at worst, I suggest printing the middle section first to be sure, if that fits ok you know the rest will be fine. I've cut it for a Rep2 size platform , in 3 sections but I included the full mask incase you are lucky enough to have a large printer and can do it in one hit. I have made no attachment system, I figured there is a gazillion ways to attach it, velcro, elastic.. a baseball cap backwards... it's up to you really.
I figure if someone is actually going to print and paint a Palpatine costume mask, you are going to be wearing a Robe, so I have made enough of the mask to show when you wear it with a hooded robe.
***Enjoy, and may the Force be with you, Always... ***