Not too much information in this topic, but what you could do it to create a good website with much information and maybe create some landing pages. Track all the conversions ans see which performs better. Try to find what your customers want and improve your service. Go social and start campaigns. This should help you at first, after that try to follow the trends.
you can buy one already developed for cheep.. http://www.nichewebprofits.com/category/online-web-store/
Buying a developed site can be a great time-saver, but if you're feeling up to the challenge, you can pick a niche, choose target keywords, and build a site yourself. One good question is are you going to sell your own products or are you going to promote someone else's products for commission? From then on, you can go about setting up the site and driving traffic to it to convert to sales. Hope that helps. Have a good day!
First of all research on your targeted sales then come here and discuss what you are really want to create, either it is an affiliate website or its your own product's sales website. And after that it is better to hire a developer to create a sales websites.. If its only a sales website then it will not be a problem to create it because it needs sales page that would be your landing page aswell. I prefer Wordpress CMS to use to create Sales website. Its easy and comfortable to use and understand.