Texture
I often feel like texture can really make or break a design I am working on. Or even a design I am viewing. Texture lends a great deal of depth and makes a viewer make a connection to something in their past to the design they are looking at now. Just by looking at the texture, and knowing how it must feel. You look at something with furry texture, for example, you know it is soft and cuddly. Same with smoothness or roughness. Juxtaposing a message with a texture that’s the opposite can also have an unexpected effect. Useful if you’re trying to create a message about the two things you’re juxtaposing.