Question: Every time I go walking or hiking, I generally spend most of my time looking down to make sure I don't step on a snake or hole or dog poop. I don't do it consciously, it just happens. Obviously, I miss out on a lot of birds and small animals up in the trees and I'd like to see how other people cope with the urge to avoid obstacles and just enjoy their surroundings.

How can I go walking and hiking without constantly looking down?

Answer: 
seems to me if you're hiking for distance, then watching where you're going is really important; but if you're there to see, listen, smell, etc., just slow down. Animals don't move quickly, they pause, look around, smell, listen, then move on. Birds are always looking around for threats & food. Slowing down is good- you may not cover a lot of ground, but it will be a richer experience.
Ha ha. You can't. At least not off a leveled surface. I've struggled with this too. If I look down I miss the views; if I look up I trip. So I look ahead for a place to stop and enjoy. Then I march on, eyes on the rocks and detritus in the trail, until I reach my looky place.