The phone's owner can put the device into a desiccant, like rice, which will absorb water and help dry out the phone quickly as possible. After dropping a cell phone in water and drying it, it is important for the owner to make sure the phone is completely dry before replacing the battery and powering it up.
These methods do not always work, but they might if the water hasn't seeped too deeply inside to the inner workings of the phone. For this reason, the chances of repairing a water damaged cell phone may be greater when repair attempts are made immediately.