Here are some important tips to minimize exposure: http://mobilenumbertrackr.com/...
Keep some distance – Hold the cell phone away from body to the extent possible.
Use a headset (wired or Bluetooth) to keep the handset away from your head.
Do not press the phone handset against your head. Radio Frequency (RF) energy is inversely proportional to the square of the distance from the source -- being very close increases energy absorption much more.
Limit the length of mobile calls.
Use text (SMS) as compared to voice wherever possible.
Put the cell phone on speaker mode.
Use your phone where reception is good. If the radio signal is weak, a mobile phone will increase its transmission power. Find a strong signal and avoid movement. http://mobilenumbertrackr.com