The trail is well-marked. The trailhead is across the street from the parking lot next to Betty Lake. The full trail is fairly short, and grades are mellow. You'll descend to the lake, which means that there will be a very mild uphill in the return journey. After about 1 3/4 miles, the trail hits the PCT: Highway 58 to Highway 242 (McKenzie Pass). Head north along the PCT for a few hundred feet before turning right onto the Bobby Lake Trail, which leads you toward the lake.