This is the only practical way to the summit. The hike is short, but time consuming due to the brush and route-finding.
See the main page for details.
Walk the road into Hughes Canyon past the first corral and windmill, coming to a second windmill about a half-mile later. The road ends here. Follow a footpath east until it peters out in the high grass.
Aim for a subridge coming off the main south ridge. The one you want has a rocky knob about half way up. Getting there requires dropping into the drainages, battling very thick brush (cat-claw, cactus) and loose rock. You may have to "guess" when to exit the drainages to get onto the right slope. Expect to backtrack here and there.
Walk up the steep slope to the rock knob. Some minor rock scrambling may be required here. Continue up past it to a smaller cliff band onto the main ridge. Again, some small class-3 scrambles on loose flaky rock is required. Exposure is minimal, but your real concern will be the agave and cactus should you slip or fall.
On the south ridge aim for the summit. You can hike to the base of the main cliff band, then traverse right to where the cliffs ease up a bit. There are many options to scramble up, generally about 20-foot climbs on class 3 rock, with a little exposure (not much).
Once atop the cliffs, hike carefully up the loose rock and thick scrub. You have to battle your way nearly to the very top.
Long everything, plus gloves. You will get torn up with the cat-claw. Pack in all water. A pole may be useful for balance on the loose slopes and probing for snakes.
On my first try in 2007, we hiked up the west ridge, which was very easy, but it comes to cliffy obstacles fairly fast. There may some ways through this, but I cannot comment specifically.