Its not easy to imagine a way to shield Earth of the accumulating heat from the Sun. We have seen a serious acceleration of warming and its not clear if this will result in more radiative cooling, in other words if this is stabilized at this moment. The problem is that heat accumulates in the oceans, it builds up because the atmosphere above it reflects radiation back (because CO2 absorbs it) which would otherwise have escaped to space.
It is not entirely clear what our options are, whether Albedo increase is a real solution and in case it is in what way. We basically have no good models yet of actual effects, only ballpark estimations. A fundamental truth is that all radiation that does not reach our atmosphere will not warm it. So how can we ‘regulate’ that?
The idea is pretty simple, first of all you don’t try to stop all the light everywhere, but only around the equator. After all we are seeing hot temperatures because of desert heat blowing to the North. This is the heat of equatorial deserts. If we can reduce the insolation (solar power) around the equator that is a plus. How? By lauching reflective flakes into space.
The flakes can be metal but it is possible to make highly reflective material using polymers, which are also lighter and easier to come by (less energy intensive to make). Next step is to launch them into an orbit around the equator, at a respectable altitude. We use a starship for that, but a Falcon 9 can probably also achieve some results. A third alternative is to make flakes on the Moon or elsewhere, the advantage being that launching them into an Earth orbit is easier.
Non metalic flakes will not block radio signals
The flakes will simply float at 17.000 km/hour around Earth (That would be geostationary) or smarter still move around Earth along with the Sun, a so called Sun Synchronous Orbit (SSO) this minimizes the material needed. It will be like there’s a dark spot in the center of the Sun, but really it will be hard to notice because the sun is still very bright.
The flakes will be in some orbit around Earth, and will slowly fall down. To keep them up there we can deploy lasers or directed sunlight, so that somewhere along the equator there is a station that will hit them from below, pumping them to a slightly higher orbit. It can be a good idea to make the top white (or silver) and the bottom black, so that the bottom absorbs any radiation and sends at least 50% out to space. The top will send most radiation back to space.
Flakes can be added and because it will take some time to see any effect their amount can be precisely determined. After a while they fall back into the atmosphere, so no harm done!