I have a little bit of hearing loss so would like to be able to turn up the incoming call volume. I can't figure out how, unfortunately.
With the phone facing you and the hinge at the top, look on the left side of the phone. The same side as the recharging port. At the top of this left side, there is a very slim rocker type button that will allow you to turn up the volume. I did mine by pushing the arrow up button a few times and then using another phone to phone myself. You can keep doing this until you find a loud enough volume - you might want to consider changing the ringtone also - some of them are much more attention getting than others.