Ideally, the color scheme of your banner should be highly contrasting in comparison to its placement. ... When designing your banner, make sure to really think about the copy that is and isn't needed. Try to remove anything that is unnecessary and communicate your message in the most simple way you can.
One of the most important elements in the banner ad is the value proposition: what you're offering your customers and the words you're using to “dress” up your offer. A good value proposition attracts your users' attention, it gives people an incentive to click and it gets them on the path to conversion.
Banner design is a fundamental component of online branding. When marketing a business' products and services, catering to the visual component of the target audience's purchasing intent and behavior is a crucial factor. Banners are among the most prevalent forms of graphic design used to market services at present.