If you're proficient at reading USGS topographical maps, you should have no trouble following these directions. For more detailed directions see the Tikaboo Peak Map on this site.
You'll need the 30x60 minute Pahranagat Range, and the 7.5 minute Badger Spring.
Head up Hwy. 93 from Las Vegas (Apex) and watch for the Pahranagat National Wildlife Refuge (if you come to Alamo, you've gone too far). You'll want to head west on a dirt road right between the upper and lower Pahranagat lakes (mile marker 32.2). Head out on the dirt road, turning north through Medsger Pass, and across Badger Valley to Badger spring (close to 20 miles of dirt road).
From the spring it's really only four-wheel drive (or really crazy two-wheel drivers). Continue to head up the road (wash) and bear to the left and up the steep road (ravine) to a campsite in the saddle above. This is a great place to camp if you don't intend to do this all in one day.
From the saddle campsite head up the road (trail) that's been blazed to the south / southwest. You'll be climbing a "false summit" first, so head up the scree slope following the trail marked with rock cairns. Go left of the large rock outcropping at the top, following the trail down into a small saddle. It's easy to loose the trail at this point, but if you head up to the top of the ridge in front of you, turning right at the ridge-top, then you can proceed up the ridge to the summit.