Explain the four principles of effective design

What will be an ideal response?

Answer: Consistency: Throughout each message, be consistent in your use of margins, typeface, type size, spacing, color, lines, and position. In most cases, you will want to be consistent from message to message as well; that way, audiences who receive multiple messages from you recognize your documents and know what to expect.
Balance: Balance is an important but sometimes subjective design issue. One document may have a formal, rigid design in which the various elements are placed in a grid pattern, whereas another may have a less formal design in which elements flow more freely across the page–and both could be in balance. Like the tone of your language, visual balance can be too formal, just right, or too informal for a given message.
Restraint: Strive for simplicity. Don't clutter your message with too many design elements, too many colors, or too many decorative touches.
Detail: Pay attention to details that affect your design and thus your message. For instance, extremely wide columns of text can be difficult to read; in many cases a better solution is to split the text into two narrower columns.