Once on the southwest side of Symphony Lake, look to the mountains directly west for a broad mostly tundra slope with a saddle at the top. After a 1600 foot climb you will reach the saddle where you can see the North Fork of Ship Creek. At this point you can either drop about halfway down to Ship Creek to find an old horse trail. Follow the horse/animal trail to Rendezvous Pass where you will climb over into the South Fork. Once over the pass, the trail will take you back to the parking lot.
The other option is to turn northwest to follow the ridge(s) and eventually drop down into the South Fork Valley. Depending on where you drop from the ridge, you should eventually intersect with the trail to the South Fork trailhead parking lot where you started. This is a hike for clear weather as you will need to have good visibility to see the route on the ridges. There are a number of ways to go. You will need to be adept at route finding and navigation as there are no trails on the ridge. The horse trail below is badly overgrown in areas and very difficult to follow. Happy Trails!