To begin, you're going to have to choose a trailhead. You can walk the Crest portion first, or the Loop portion first. The East Trailhead which begins the Crest portion is located on the top of Crag Crest, off of Forest Road #121 near Eggleston Lake, and offers you and your doggo a more challenging hike at the start. This section is popular with hikers who'd rather get the difficult parts out of the way first. The crest portion of the hike is the longer section as well. This 6.5 mile trail is sometimes hiked by itself, either as a point to point or an out and back trail. The advantages of tackling just this portion of the trail depend on what you value. If you're in hikes to be on top of the world, you can't beat this portion. It offers amazing views down to Aspen forests and much of Grand Mesa National Forest.
The West Trailhead has a more gradual climb, and is where you can access the loop. On the east end of the area, off of Colorado Highway 65 and across from Island Lake, this section is good for hikers who like sustained effort or need to warm up. Either trailhead had limited parking nearby, so you can plan accordingly. The loop itself is a much shorter, 3.4 mile section. You can walk along it one way in order to bring yourself back around to your original starting point. Though less popular than the crest portion of the trail, some people do only hike the loop. Mountain bikes and equestrians are both allowed on the loop portion, but not the crest. Motor vehicles are prohibited on the entire trail, so that's one thing you don't have to worry about sharing the road with!
Crag Crest Ski Trail is a pupriffic hike, no matter what the weather's like!