Web designers are well versed in the principles of visual design and are proficient in the following things
Composition. You need to understand how to lay out websites with organized information using a column grid, vertical rhythm and module, and be able to adapt the design to different screen sizes – create a responsive design.
Typography. Practice choosing font pairs that fit the brand’s voice and match, easy to read, eye-catching and energizing for targeted actions. Stick to one or two main fonts with a wide range of weights and strive for consistency in your design system.
Color theory. Color helps create a mood and set the mood for a website visitor. Study the psychology of color, explore the effect of color combinations on feelings.
Visual design is a whole science, we cannot cover it within the framework of this article, but here you can find more useful information at this resources
- Basic rules of modern digital design
- Basic Principles of Graphic Design for Non-Designers
- Short UI Tips: How to Make Your Website Design Significantly Better
- Free online course “Getting Started in Graphic Design – How to Become a Graphic Designer”