When evaporation takes place, the average energy of the molecules in the liquid falls. Energy and temperature are directly related, so if the average energy of the liquid molecules falls, so does the temperature. When this happens on your skin, you feel a cooling effect.
Evaporation can be increased by:
o Increasing temperature so that more particles have enough energy to escape.
o Increasing the surface area of the liquid so more molecules are close to the surface.
o Reduce humidity level so that air has more capacity to absorb liquid.
o Blow air across the liquid surface so that liquid molecules above the liquid are less likely to reenter the liquid.