If coming up I-70 from the Front Range, drive on through the tunnel. Get in the right hand lane while driving through. Immediately upon exiting the tunnel you will see an opportunity to exit the interstate on your right. Do so and drive over to an area where you can park out of the way of semi's and other vehicles. You will see a road that heads off to the east and goes up behind a building. Park near that road. It will serve as the beginning of your trail.
If coming from the west on I-70, just before arriving at the tunnel entrance, exit the interstate on your right and rive past some small building. The road you're on will climb up a little and circle above and around the tunnel entrance to bring you back down to the suggested parking area on the north side of the interstate.
There is no designated camping in the immediate area or for several miles around, neither is there any good primitive camping close by. For Front Range hikers, this will not be a problem. For western slope hikers, you may have to find whatever camping you can much farther away.