A mood board, or an aesthetic board, is a collection of images meant to give an overall impression of a theme using color and imagery tied to that theme. I make these boards by finding and saving images from google searches and then making a collage of them by cutting and pasting, resizing, flipping, and rearranging in Microsoft Paint. There are other easier methods that can be employed, make them however you would like! The whole idea is that this is a quick and easy way for anyone to be able to artistically express themselves. It may be a handy tool to reference your mood when looking for inspiration to write, draw, or roleplay your character.
For an example, here is a board for my retail RP character Kerala Windchaser:
Kerala's preferred color was blue. She was a druid who loved flying more than anything. Apples were her favorite treat and she had a wild curly mane. She was extremely stubborn and refused to back down from any fight or cause she believed in. I won't give away all the details about her and her story, but you can get the idea.
You can describe the mood board like this if you wish, but I enjoy them most when no explanation is given!
More examples as well as the inspiration for this activity can be viewed
HERE.
Jam