Follow the gravel road from the parking lot, and make a right immediately after the gate. Up Chuck climbs along the edges of Camp Sekani using a mix of single and doubletrack trails.
This trail is primarily used as a climbing trail - the berms provide nice support for climbing and descending. The trail can be a little confusing as it moves from one trail type to the other. You'll want to stay beneath the dirt jumps, and stay to the left above the skills park. The trail ends next to the base of the Rushmore feature.
Up Chuck provides the best route to the top of Sekani, but riders could also use the access road that leaves from the dirt jumps.
The bottom half of Camp Sekani is also home to a disc golf course, so keep an eye out.