Here's my pile of un-ironed pillowcases.
Here's my little helper, Magic Sizing. I found out about this "magic" spray when I eavesdropped on a conversation two old ladies had with each other while on the laundry isle at the grocery store. They were extolling the virtues of Magic Sizing and how it made all the difference in their ironing. Well, as soon as they moved on, I moved in on the magic stuff. I snatched up a can and used it as soon as I got home. That was 23 years ago and I haven't done any ironing since then without it.
I use my iron on the cotton setting and use a medium amount of steam. Here is one of my pillowcases with the "before" on the left and the "after" Magic Sizing on the right.