Tarps

From Burnwiki, a Burning Man Wiki & Brain Dump

Not all tarps are made alike. The most easily available ones (and the cheapest) are blue plastic, and are available in virtually every hardware store. These are OK, but don't completely block out the sun, and the grommets are likely to rip out during a dust storm. Of the genre of plastic tarps, the best ones are heavy-duty silver. The 'silver' won't do much in the way of actually reflecting the sun, but the tarps are thick enough to completely block it out, and stand up to the stress of high winds.

If you're looking for shade, take a look at some other fabric options:

• Aluminet reflective shade cloth
• Reflective space blankets
• Parachutes for domes
• Shade Cloth