Back in the early years of internet it was more than enough just to write a few sentences on your webpage and upload an image or two in order to receive a massive amount of web traffic. But nowdays things are completely different and, if you want to get the same amount of high traffic, you have to focus on more issues, which are all part of the so called "web design".
As stipulated in the Google guidelines, these web design issues refer to the relevancy of your website to the visitors' search query, to the transparency of your website regarding the nature of your business and to the navigability of your website. Taking those issues into consideration when designing your website will improve your visitors' experience with it, so you will build trust in your business; and you know what that means from the sales' point of view.
Knowing those important design guidelines, you are able to design your website yourself. But if you feel you do not have enough experience to deliver a real competitive "product" on the market you could hire a professional web designer or a company to do it for you. Either way, there are some key elements which will increase your profit when used properly.
First and foremost, it is very important to set your main goal. Whether that would be a sale, an e-mail registration or viewing a specific page on your website, your website must have a goal. After choosing the goal, make sure you entice your visitors to follow the path to that goal; use dynamic words, always refer straight to the visitor using "you" and keep the text short and to the point. Do not expect the visitor to know what he is supposed to do; use a strong call to action, like "join now" or "learn more", to pursue his buying, registering or viewing a specific page. Also help the visitors to buy, register or view that specific page and simplify the path to that final objective.