I briefly had an Etsy shop for selling crafts, but since I didn't promote it much, I didn't sell much. My husband sells slotcar drivers over the internet through his website
http://immenseminiatures.com/ which he promotes via Facebook and various model forums. Success comes with constant promotion - you have to get your product out there in front of potential customers every single day. You might want to start by opening a shop on Etsy or similar venue, to practice selling before you build your own website. Decide on a business name you like and stick to it. A nicely designed logo is useful. Business cards can be helpful, and you can even print them at home. Depending on what you're selling you might have to invest in special packaging such as boxes and bags.
I hope this helps a little!