What are some important aspects of visual design?

Colour; choose compatible colours with high contrast. Avoid red/green, blue/yellow, etc due to colour blindness. Add redundancy, e.g font, flashing light, etc. Font; conveys information. Some are easy to read, some not. Some need to be read quickly (driving) Layout; Group linked suggestions together. Layout within and between screens. Consisten layout. Representation; Need to present informatioj in a way that highlights whats important. Symbols and Iconography; Most are international (save, bin, power). Usually have reduntant label and follow good guidance on colours.