It's not smart to expose a lot of leg because of the cacti, and it's smart to wear bull-hide boots because of the rattlers.
That's what the people walking in front are for: clearing the path.
In all my time in the Mohave, it was jeans, log sleeved but loose fitting shirt, and really good, high boots. Don't reach over/around/under anything you can't see, and better yet, at least 'adopt' a walking stick/staff for the trip.