In general, which designer aids actors the most in them discover the psychology of their characters?

"The costume designer" aids actors the most in helping them discover the psychology of their characters.

is a man who plans costumes for a film or TV etc. The part of the costume designer is to make the characters' outfits and adjust the scenes with color and shading, etc. This helps the actor feel real in the character they are to play in the scene. 

Pilgrims is the answer