Overview:
This route could be done in two or three days, or you can keep it easy by hiking four easy days.
This route starts at Tenaya Lake and ends where 120 crosses Yosemite Creek, so it may be best to leave a car at the end before beginning. Parking at Tenaya Lake is on the shoulder of the road, and the shoulder gets crowded on a busy weekend in the summer.
Elevation gain on the first day is moderate (~500', with about 1100' of climbing on the second day to the pass just north of Toulumne Peak, with great views of the Tuolumne Valley to the north.
On the third day hike into a beautiful canyon, descending 1400' and ascending 1100' to the Ten Lakes area. This is the hardest day, but it is very scenic.
Tips:
Basic backpacking gear: tent, sleeping bag, food, etc.
Don't forget: water filter, mosquito repellent, bear canister, camera.