Limit Your Cell Phone Use to Where Reception is Good:
The weaker the reception, the more power your phone must use to transmit, and the more power it uses, the more radiation it emits, and the deeper the dangerous radio waves penetrate into your body. Ideally, you should only use your phone with full bars and good reception.
Also seek to avoid carrying your phone on your body as that merely maximizes any potential exposure. Ideally put it in your purse or carrying bag. Placing a cell phone in a shirt pocket over the heart is asking for trouble, as is placing it in a man’s pocket if he seeks to preserve his fertility.