If my piece of content is so unique and valuable around hiking backpack recommendations, that other reputable outdoor websites are willing to link to it and build the page’s authority, then I’d have a very real opportunity to rank high in organic search for these search terms (meaning, my page will come up first when someone searches for hiking backpacks).
Provide excellent customer service. Answer any questions buyers post as quickly as possible. Be professional and courteous. Positive communication builds your reputation with buyers and gets you return business. Also, package your product well and ship it out quickly. Allowing an item to become damaged or taking too long to ship can negatively affect your reputation among buyers. Wrap all items, especially fragile ones, in appropriate packaging. Commit to shipping items as soon as you receive payment.
As someone who's been immersed in a number of online industries for quite some time, I know a thing or two about what it takes to succeed in this arena. However, just like you, I started at ground zero with little knowledge, but a great deal of passion. What I learned along the way were some invaluable lessons from failure that hurt at the time, but helped immensely in the grand scheme of things.