which is pretty ineffective since mosquitos are quite good at finding the body part that's uncovered. If you sleep like a cocoon and don't move i guess that works.
Point the fan at the uncovered part. Mosquitos tend to dislike fan airflow. Also works outdoors. The airflow also triggers your pressure sensors so spontaneous firing isn't an startling issue if the fan breeze hits something other than your head.
Obviously for use in the hot summer; also if you sleep with a fan pointed at you in Korea, you'll catch fan death and die. Cultural myths about fan death is an interesting sleep related topic. With respect to nature vs nurture, different cultures certainly do weird things such as fan death related to sleep but the vast majority cross culturally like blankets; that would imply blankets could be genetic in some weird way not merely cultural.
If only your face is uncovered, I think you are more likely to notice a mosquito, either by sound or by touch. On the other hand, mosquitoes can reach you through a net or thin sheet if it is against your skin, as I have found to my cost.
