Space umbrella
To prevent warming, you need to make a sun umbrella. This is a grille made of high-quality plastic (temperature from minus 100 to 150 degrees Celsius in space). The cells (50x50cm) should be folded diagonally and collected into huge strands. Graphene material must be fixed to the lattice cells.
These lashes, more than half the circumference of the Earth, gather on the Moon.
And by space bots they are delivered to Lagrange points opposite the Sun.
The width of the unfolded lash should be so that it immediately covers at least 30 degrees of the Earth’s area. And thus the entire surface will be shaded. That is, gradually.
Control of space bots must be carried out from Earth and maintenance, if damaged, by a team of astronauts on space bots.
All this can be done with funding from all states of the Earth, and the work can be done jointly by the states of Russia, the USA, and China with the help of other participants who have success in space.