If anyone is planning on day-tripping to be under the total eclipse, prepare for the worst traffic you ever thought possible.
I was out in western Nebraska for 2017 and all these rural two-lane routes that are normally several minutes between vehicles driving by were bumper-to-bumper. Easily the most traffic those particular roads had ever seen and will ever see. My advice is, wherever you set up to watch, just chill out there for a few hours and let everything clear out. Why put up with the hassle? Bring a portable grill and cook out. Have some lawn chairs, especially the kind that lean way back, fill a cooler with some taste beverages and settle in.
If you can make it, totally do it. It's pretty cool, both metaphorically and literally. After about a minute of totality you start to notice, "Hey is it getting cooler?" You wind up talking with the folks around you, snacks get traded, beverages get shared. It's a rare collective experience you will never forget. I even saw some disaffected teenagers who were clearly dragged along for the trip to rural Nebraska snap out of their cell phone immersed existence and have a real, profound moment.
There's something very primal about gathering with thousands of other humans in the middle of nowhere and all simultaneously cheering the eclipse at the moment totality begins. You feel connected to something ancient. Like this is some kind of ritual our ancestors would do long before the invention of science or monotheism. That sounds a little pretentious and stupid in writing, but maybe you'll have a similar feeling after you experience one.