Smith Mountain is on the Kern Plateau, near Kennedy Meadows. The highpoint of about half dozen small peaks in the area surrounded by pine forests and lush meadows, Smith is probably the most climbed of the lot. The peak is mostly tree covered, but the summit is topped by a small granite formation that requires some class II scrambling on excellent rock covered with pretty lichen.
This is one of the less visited parts of the sierra. Probably the most common users of the area are the motorcyclists. There are hundreds of miles of trails open to them on the Kern Plateau and you will occasionally here them motoring through the forest.
From highway 395 near Pearsonville, take the Kennedy Meadows road (22S05), to Kennedy Meadows, then keep going until you reach the intersection with road 21S03 at the USFS Black Rock Station. Turn right and go 3.6 miles and turn right onto USFS road 21S36 (the sign says "Monache Jeep Road 4 miles"). Go 5.8 miles on 21S36 to the dead end and park.
From the parking area, walk up old logging road about 3/4 mile to where it crosses a motorcycle trail, Turn right and follow it a short distance (couple hundred yards), then leave the trail to the left and cross-country up the tree covered ridge of Smith Mountain. There are some cairns but no trail. It's an easy hike, about 3 miles roundtrip.
If you want to have a campfire you'll need a USFS fire permit. You can get fire permits and information at the Black Rock ranger station.
You can camp anywhere you want. There's lots of good spots if you want to hike in, but water is scarce, or you can car camp at the trailhead, or find other good spots along the road before the trailhead. There are no facilities so bring whatever you will need.