Take the Flattop Mountain Trail from Bear Lake as described on the mian page. Once on top of Flattop Mountain, take the social trail south along the broad expanse between Flattop and Hallett. Then follow the trail to the summit. Hallett had wonderful summit that provides views of just about every peak in the Northern two thirds of the National Park.
The difference in route happens on the way back down the mountain. Come down the exact same way you came up, until you come to the hitch rack for livestock just below the summit of Flattop. You will want to head due south, down the very steep South slope of Flattop. You will see the Pool of Jade far below.
Pic the best route down. TAKE YOUR TIME. I had to go down, then back up, down then back up etc... because some routes that look "right" end with a large drop off. The only time I have done this route, I came to a small drop of about 10 feet, which I had to jump off of. This was the smallest of the cliffs I could find.
Once you find a route that looks passable, try to plan the rest of the route all the way to the bottom of Tyndall Gorge. Watch for springs seeping from this slope. There were a lot of wet, slippery rocks.
Once at the bottom of the Gorge below, pick the best route through thick wildflowers and many meandering streams. Again, wet rocks are very common, so keep you eyes peeled.
Follow Tyndall Gorge all the way to Emerald Lake. Then pick up the Emeral Lake trail and follow it all the way back to the Bear Lake parking lot. (1.8 miles to the parking lot from Emerald Lake)
Basic hiking essentials. DO NOT forget your camera!!
Once in Tyndall Gorge, you will be rewarded with many wonderful scenes of waterfalls (literally hundreds), and millions of wildflowers!