Head up the singletrack after about 0.6 miles look for a T which will take you to a paved road. Ride up the paved road by a campground and onto the East Fork ATV trail.
East Fork ends at the Scout Mountain Top road. Go left on the dirt road and follow it until to the Crestline trail, which will be on the right. Hit Crestline downhill until you get back to the singletrack you started on.
There's about 2,200 verts of climbing to start in about 6.2 miles. After that, it's a quick downhill.