Educate yourself about the RF sources in your home, and replace the devices that you can with non-wireless alternatives, and replace the wireless connections that you can with wired ethernet or other cord/cable connections. Note: most wireless devices can connect non-wirelessly, sometimes an easy-to-find adaptor accessory is required to use cords/cables.
The research continued, and what it uncovered would be a dire warning to cell phone users and the industry’s worst nightmare. When the findings were ready for release in 1998, the scientists were suddenly confronted with another challenge: the industry wanted to take over public dissemination of the information, and it tried everything it could to do so. It was faced with disaster and had a lot to lose.
Don’t rely on a “radiation shield” or other products claiming to block RF energy, electromagnetic fields, or radiation from cell phones. According to the U.S. Federal Trade Commission, products that interfere with the phone’s signal may force it to work harder and emit more RF energy in order to stay connected, possibly increasing your exposure. It is best to use wired solutions to reduce RF rather than rely on an untested product.
This substantially changes the debate on whether cell phone use is a cancer risk. Up until this point, the federal government and cell phone manufacturers operated on the assumption that cell phones cannot by their very nature cause cancer, because they emit non-ionizing radiation. Whereas ionizing radiation—the kind associated with x-rays, CT scans, and nuclear power plants, among others—definitely causes cancer at high enough doses, non-ionizing radiation was believed to not emit enough energy to break chemical bonds. That meant it couldn’t damage DNA, and therefore couldn’t lead to mutations that cause cancer.
Then there is non-ionizing radiation, which encompasses the vast majority of light we are exposed to: visible light from lightbulbs, infrared light from an oven and from people, gigahertz light from our wifi, megahertz light to/from our cell phones, and radio waves hitting our car radio. They are not harmful in small doses because one photon does not have enough energy to ionize atoms and/or break apart molecules. In very large doses, non-ionizing radiation can be harmful. For example, a visible light laser with sufficient power (at least several hundred times more than a legal laser pointer) which is concentrated in a small enough spot will burn your skin and do worse things to your eye if it gets in there. And those of us who are old enough, remember the gerbil-in-a-microwave flash animations which went viral 17 years ago  as a humorous (but not exactly factual) representation of what would happen if you microwaved a live rodent.
The energy of electromagnetic radiation is determined by its frequency; ionizing radiation is high frequency, and therefore high energy, whereas non-ionizing radiation is low frequency, and therefore low energy. The NCI fact sheet Electromagnetic Fields and Cancer lists sources of radiofrequency radiation. More information about ionizing radiation can be found on the Radiation page.