Fiskars large punch is 3/4", the extra large is 1".
I punch a hole in the middle for easy removal and baste, but only the corners, never thru the paper. Finger press as you go and a quick press with the iron, once sewn together you only have to quickly pop out the papers, the basting in the corners stays put. I've made EPP and hexi quilts for over 30yrs and tried every method, this is the quickest by far.