This is not so much gear oriented, but logistics. Yosemite in June is very crowded. Driving around can be done, but parking is tough and you might find yourself sitting in traffic instead of being being the lens.
We bring bikes to the Valley and they offer a quick way around pedestrians and autos. There is also the bus system. If you really want to leave people behind, you will need to hike. Early starts for popular trailheads are a good idea.
Have a great visit. Yosemite Valley is one of the wonders of the Earth.
