The walking route will begin from where the South Colony Lake Road crosses South Colony Creek at 9,980 ft., with the assumption you have a vehicle that will get you that far. If you must park and start from the fence line at or below 9,000 ft., add another 2.6 miles one way.
Parking for vehicles is before the creek crossing. There is a footbridge to assist getting across the creek. From where the road/trail crosses to the north side of South Colony Creek, hike west up the old roadbed for 2.8 miles to where the road use to end and there is a level area. You should find a signed junction here. Proceed by either of two trails up to the lower of the South Colony Lakes. The trail that continues SW along S. Colony Creek is a little longer in mileage. Both are Trail #1339. The Trails Illustrated map does not show the shorter trail. The San Isabel NF map does show both. The more direct trail crosses a rocky area after about a half mile, having passed through forest and continues in more forest, then willows as it arrives at the lower lake.
Regardless of how you get there, make sure you pick up the correct trail #1339 on the east end of the lower lake. From here, there should be no difficulty in following the well-defined trail that first heads up to the upper lake where you'll turn right at another junction to hike to the saddle west of Humboldt Peak, improved by the efforts of the Colorado 14er Initiative. Most of the elevation gain will occur here. The trail does pass through some willows so be prepared when it's wet.
Once you gain the saddle west of Humboldt, turn west and follow the ridge crest to an east-west running ridge with a high point of 13,290 ft. marked on the USGS map at the east end. Once you've gained about 400 feet, hike on the ridge crest. Your westward progression will be expedited by staying as much as possible on the top of the somewhat loose ridge with occasional drops down mostly onto the north side. The mostly rocky ridge offers just enough difficulties to slow your progress some. Once across it, drop down onto the "Bear's Playground" and descend a little north to a saddle. From the saddle, it's easiest to follow tundra as long as you can to the summit ridge east of the summit, rather than make a beeline for the summit, aiming for the summit of Obstruction Peak. The initial part of the hike will be on mixed tundra with embedded rocks/boulders which will give way to boulder rubble as you gain elevation. The finish will be on nothing but rocky rubble to the uneventful summit. Most people with more interest in climbing the 14ers will simply skirt below Obstruction Peak. You would be well-advised to go ahead and tag this summit on the way to Kit Carson, as well as Columbia Point, which you almost have to climb to reach Kit Carson.
To interject a little story here, we climbed this summit on a late June day that began with a cloud-filled Wet Valley. Back in 1995, we were able to drive all the way up the South Colony Road, but even then, it was so rocky and slow, it barely saved any time and ended up costing us a set of shocks. The low-water crossing of the creek was a thrilling experience with water trying to come in around the doors and washing up onto our hood of our Jeep Cherokee. (A few years before we had driven this road and I had sworn then I would not subject my vehicle to it again.) Almost all of our hike was in clouds which by the time we were hitting the Bear's Playground, were organizing into a thunderstorm. The final spurt to the summit was an electrifying experience, being perhaps the worst electrical storm we have ever been caught in. Lightening strikes were occurring about every one to two minutes as we made a mad dash for the summit that we found abuzz with all the electrical activity. We spent all of about 15 seconds there. Then, on the way back across the east-west running ridge, we were constantly listening to the rocks buzzing, crackling and sounding like bacon frying in a skillet. We offer this account mainly to make the point that once you reach the Bear's Playground, there is no place whatsoever to duck out of such a storm. If you think one may be approaching, wait it out in a safer location!
Links to other information, routes & trip reports for this peak that may be helpful.