Begin at Yeoman Park Trailhead. Start with cross country wax but keep your climbing skins handy. Carefully identify the start of the Hat Creek Road. It begins just west of the actual campground and follows a distinct road-cut up a SE-climbing traverse. Follow the road to the first switchback and continue climbing NW through several more switchbacks. Stay on the road; at 9,400 feet you'll swing S into the Hat Creek drainage.
Once in Hat Creek, the route continues to be obvious and well marked. Basically you stay on the main snow-covered logging road as it parallels Hat Creek. The only deviation from the creek takes switchbacks starting at 9,800 feet elevation. At a 10,820-foot saddle (Ironedge Saddle) at the head of the Hat Creek drainage, the logging road makes a turn to the south. Leave the road here, ski several hundred feet farther E, and intersect the continuation of the Ironedge Trail that 10th Mountain has marked. Climb this trail 3/4 mile SE up through timber to the Peter Estin Hut. This section of trail is less obvious than the logging roads, so pay attention.