Take exit 282 after "town" of Carlin. Turn right off freeway ramp, immediate left onto frontage road. About 1/3 mile down, the road curves back under the freeway and you enter the canyon. There are a couple of pullout parking/camping areas. I used the second one on the right, maybe 1/2 to 3/4 mile on the right after you go under the freeway.
Note that on the map it looks like you can continue on that little road and get on freeway at the next "exit" but it is all blocked off. You have to retrace your steps back the way you came to get back on I-80.