During evaporation particles of the liquid gain energy from the surroundings to overcome the force of attraction between them 

as a result loss of heat energy occurs in the surroundings 
that is why evaporation causes cooling 
if we pour some acetone on our hand we will fell cool because the particles gain energy from our hand to evaporate 

thus evaporation causes cooling
During the process of evoporation,the water gains energy from the surroundings and this is the reason why evoporation causes cooling..
During evaporation water evaporates and changes into water vapour.for that heat is takenfrom its surroundingsso it produces a cooling effect
When a liquid evaporates it absorbs heat from a surface in the form of latent heat