Print on Demand
I am actually building a site very similar. Instead of photographs though, it is prints of paintings. I don’t have this set up for print on demand though. I find it cheaper to just partner with local print shops as there are typically hidden costs such as shipping being incredibly high. So when someone makes an order I submit the order to be printed from whoever is currently cheaper on my list of places to print from. Sometimes they have specials going on so it is nice to be able to adjust when needed. This process also can be automated depending on who you use. Shopify has some app integrations you can use such as: JetPrint: Print On Demand (Free). If you look up Print on Demand in the app store you can look through the reviews to get an idea of the good and bad of each service. Most of them also have free trials.
SEO
For on page SEO here is a boilerplate for your metatags. You can compare what your code is inside your theme.liquid file ones you decide on a theme:
Optimizing your website starts with the foundational technical setup, but the real impact comes from strategic content choices. Key to this strategy is a careful selection of keywords and crafting a compelling description.
Incorporating terms such as “photography” and “print” directly into your domain name can significantly boost your search engine visibility. An effective tactic for local targeting is to include your hometown in your domain name, which can make your site more relevant to local searches.
I often employ the strategy of acquiring multiple domains related to my niche, which in my case is small square paintings, and redirecting them to my main website. For example, my primary website domain is littlepaintingprints.com (currently in the setup phase). Once operational, this domain choice will naturally attract traffic from searches for “little painting prints,” leveraging the fact that search engines place considerable importance on domain names. This advantage is surprisingly under-discussed in SEO circles. Moreover, if the exact phrase is used elsewhere on the web, search engines might associate those mentions with my site, potentially generating valuable backlinks.
Beyond domain strategy, it’s crucial to optimize your product titles, descriptions, and page names. These elements should align closely with the terms your potential customers are searching for, creating a direct pathway for them to find your offerings.
Always try to think in terms of what people would be searching for and try to use those phrases within your products. I do this in the reverse and actually create paintings specifically because they are a niche market.
Free Marketing
Market your products on Google Shopping for free. Shopify has easy integration for that. You can also link your products to Facebook, Insta, Pinterest and actually sell directly on those platforms as well. Shopify also has very easy ways of syncing this data.
Paid
Google has paid ads but it is per click so it is important to learn as much as you can before spending a dime on paid marketing. Something that might be better for your market is Instagram as it is literally designed for people that like photography. Reddit is also very under utilized for marketing.
Theme to Choose
I am a developer so this is a hard one to answer for myself as I end up custom making my sites. You’ll want to figure out what your branding is as this will be the largest difference between paid themes. Most of them are extremely similar in functionality. Maybe someone else will have a more informative answer for this.
A good photo organizer app is Mylio and Adobe Bridge but this is for local storage. Shopify does also store your products and has a great way to organize products into categories for organization inside Shopify.