From the top of Guanella Pass, find the trailhead near the restrooms in the upper parking lot (on the west side of the road) Photo #1. Do not follow the crowds, most people will be heading towards Mt. Bierstadt (on the east side of the road). Shortly after starting, a sign Photo #2 will direct you toward Square Top Mtn and Square Top Lake. Hike through the well marked trail over several wooden bridges - Photo #3. Mt. Bierstadt and Mt. Evans will be visible behind you for most of the trail - Photo #4.
You will come to a fork in the trail with a sign directing you to continue straight to Square Top Lakes in Photo #5. (Heading left will lead you to the Southeast Ridge - Class 1 climb; see other route here). The trail remains well marked for a little while longer - Photo #6, but will eventually end once you near Square Top Lakes. Photo #7 shows the trail near the end and shows the way up to the summit via the Northeast Ridge.
Approach the Square Top Lakes, and the trail will have disappeared - Photo #8. Ascend to the top of the ridge by heading northwest where the climb is not as steep. Photo #9 shows the view half-way up the ridge looking down. One you reach the top of the ridge, head southwest toward the summit. Photo #10 shows the terrain is not as easy and will require some scrambling at times. Continue up to the summit, but donít be fooled by the false summits, such as in Photo #11. Photo #12 shows the view from the summit looking east and Photo #13 shows the view looking west.