Easy.
Launch them in a container programmed to discharge them when it reaches the L1 point. They'd be scattered into a lens/umbrella naturally by the balancing effect between the Earth and Sun's gravity-pull.
Same for the ball-bearings.
We KNOW how to plan launches to Mars, so L1 should be a breeze. Launch them in a semi-circular orbit that gets them to L1 with low orbital energy left(orbital mechanics, physics). They'll be trapped there by the same balance that IS the L1.
No problemo.
RE: A proposed solution to Global Warming?