Hiking this trail requires a permit from the Bureau of Land Management. You can reach them by calling (435) 688-3246. They allow 10 hikers per day, and this area is becoming more popular, so I recommend you contact them seven months in advance of your Las Vegas trip, especially if you're traveling in summer.
Leaving the Wire Pass Trailhead you follow the wash downstream. After about 1/2-mile you will come to a gentle curve to the right where a broad, well-worn trail veers up and to the right. It climbs up to the top of a low ridge, turns south and levels off, heading toward a horizontally striated butte.
About 1 mile from the start, the trail ends just after crossing a wash and arriving at the bottom of a low, bare-rock ridge. Veer left and climb an easy gully up to a saddle at the top of the ridge. From the saddle, contour around the other side of the ridge and proceed south paralleling the ridgetop. The ridge to your right rises and you continue to head south up and over a low rise. From here you should recognize two prominent twin cones almost straight ahead of you. Head for the left side of these cones. There, about 2 miles from the start, you will cross the border between Utah and Arizona, marked by a rather desultory barbed wire fence. In the distance, almost due south, are the buttes where "The Wave" is located. There is a prominent black crack running vertically down from the summit toward the base of the mountain.
Head directly toward the crack, across relatively flat, bare rock and arrive about 20min later at a flat rock bench overlooking a wash with the black crack buttes on the opposite side. Cross the wash by a prominent black marking on the rock in the creek bed. Climb the rockface veering a little right toward a shallow, steep gully heading up toward the black crack. Stay in this shallow gully as the slope eases, and it will lead you directly to the bare rock entrance to "The Wave".
The area covered by "The Wave" is not large but you should take time to explore the various gullies where this unusual psychedelic phenomenon is most prominent. You can also climb above the contorted, wavy strata into the bowl at the base of the black crack that served as your navigational beacon.
Return the way you came, having made sure to bring along plenty of water! This hike is unbearably hot.