The last few times I've been through, sometimes they're having you remove shoes, and sometimes not. Just wear something easy comfortable, without metal in it wherever possible, and don't carry anything in your pockets you don't really need. Double check your carry-on bag that you don't have any blades of any kind... no forgotten knives or guns or ammo from the last time you carried it somewhere :~)
And it doesn't hurt to seem pleasant and unhurried at the security check. Those people deal with a lot of difficult passengers who want to take all their frustrations out on everyone around them and the screeners usually seem pleasantly surprised if you smile at them. :~)
I've never been patted down, or even slowed down much, in security.
When we were coming home from Vegas a few years ago, Mack got pulled out of line and patted down. They said it was random, no specific reason....
Becky