If you don't have a 4WD vehicle and you don't want to hike the extra 5 miles to the mail trail for the other route, than this is you better option. This route essentially takes you to the top of Daisy Pass and from there to the summit as well, but you get to Daisy Pass by starting at the Oh-Be-Joyful trailhead. This route is longer and is mainly used for backpacking. Again, don't get to distracted by the views, there are alot of careful route finding areas so use caution.
Getting to Crested Butte should be very easy, but once your there, go out of town, passing the cemetery and to the left is a sign for Slate River Road. Take this 2WD dirt road down to Oh-Be-Joyful and go all the way down to the Oh-Be-Joyful trailhead. There is a large parking area so parking should not be a problem.
So starting from the trailhead, you go through the trees for a while. Once your out of the trees you find your self going through this canyon. If you look up to your right, you may be able to see the mountain. Keep going down the canyon for a little while. Once you see that the canyon is coming to an end, you start to zig-zag up to Daisy Pass. To your right is a large rock wall that is the top of the ridge that takes you to the summit. Don't freak out, you will be going around this.
From here, there is little to no trail going across the ridge so the remaining hike will require careful route finding and safe maneuvering around small pitches as you are exposed the hole time.
Go back down the trail you came for a few feet until you get to a wilderness boundary sign. If you go about 10-feet passed that, look over at the ridge to the left. Look for a small trail that leads you to the top of the ridge. Be careful and climb up the very steep pitch, use the bushes for support on the dirt segment, but on the rock segment find a safe passage way to the top of the ridge. So now you are on top of the ridge. You can see the summit clearly. Go towards it. You will run into 3 or 4 small pitches that you can maneuver you self around these if your careful. But about half way down the ridge you will run into the main pitch of the ridge. This will be a hard class 3 to climb up. If you feel like it is to dangerous, don't attempt to climb over it. Instead go down back to the Daisy Pass route and try to bushwhack up the alternate way (see the route image on the Daisy Pass route). Once you are up the pitch 2 or 3 small pitches remain. Once you are about do your final climb to the summit, be careful, the rock is very loose. Once you are at the summit you can see most of the Ruby Range including Pyramid Peak. If you are not comfortable going down the same way, use the bushwhacking way that is listed in blue on the image on the Daisy Pass route page.
A rock helmet would be a good idea for that big pitch, but mostly a good pair of hiking books would be essential.