You'll join this trail at a junction with a register box. From here, climb uphill to the Lawlor / Strawberry Saddle Trail. The climb to the saddle is sandy and loose, making for some frustrating hike a bike sections, but it should improve with time and use. Once at the Saddle, the downhill to Redbox is fun.
This description does not include the section of trail north of the Colby Canyon Trail junction which is closed to public use due to environmental reasons.