Anyone who makes their living in the field of e-commerce will need to have a diverse set of specific skills at their disposal.
1. Have some marketing know-how.
You don’t have to be the world’s foremost expert in marketing to properly market an e-commerce site. However it is useful to at least have a basic understanding of marketing concepts and what makes your customers tick. Reading a couple of good marking books is usually a great place to start.
2. Understand Search Engine Optimization. 
While you don’t have to be a marketing expert, you probably will have to be an SEO expert (or at least work with one) if you want your new e-commerce site to succeed. There are literally billions of web pages out there. If you don’t know how to set your apart from the others and allow you site to be found you are already dead in the water. There is a ton of information on search engine optimization out there (some good and some bad). For most people SEO is a long, drawn out trial and error game. Partnering with an SEO professional that is also an expert with e-commerce can go a long way to improving your sales in both the short and long run.
3. Understand How Copywriting for E-Commerce is Different
I have written several articles on how to effectively write for e-commerce. Writing e-commerce copy requires a unique style of writing and a different perspective than you would normally have for other types of writing. I don’t want to regurgitate content so if you are interested in learning more about this topic you may want to check out the following articles:
Guide To Writing Good E-Commerce Content
Guide To Writing Good E-Commerce Content, Part 2: Advanced Topics
E-Commerce Copywriting – Thoughts on Writing E-Commerce Content
4. Have Some Technical Knowledge
You don’t have to be Bill Gates to successfully run a profitable e-commerce site. It does help if you have basic technical knowledge though (or partner with someone with some expertise in this field). Do you know what a analytics are? Can you resize an image for use on the web? Are you comfortable using a basic online text editor and learning some very basic HTML to use in product descriptions? Do you know what a hyperlink is? Do you know how to create one? Do you know the difference among different hosting companies? These are some basic technical issues that you will need to at least be aware of if you plan on taking a hands-on approach with your new e-commerce site.
5. Be Able to Analyze Results
You might think the only analysis you need to be able to perform is checking your bank account at the end of each week to see how much money your business has made, but you probably won’t be in business too long with this mentality. You should learn how to run and use some sort of analytics software along side your e-commerce website to understand how much traffic your site is getting, where that traffic is coming from and how much of that traffic is being converted to sales. A good e-commerce expert will be able to use analytics information, along with the skills listed above to modify and grow your business.
E-Commerce Expert Summary 
Hopefully at this point you have an idea of some of the broad skills you will need to obtain in order to be an e-commerce expert. These are skills that aren’t obtained over night and often require some strenuous trial and error. It is usually beneficial to partner with a proven e-commerce expert to avoid the long and drawn out learning period often associated with learning these skills.