Take a look at Greg Gottfried on Youtube. He teaches print-on-demand for free, and he's great. It's a great starting point! You can either start off with Printful or Printify. If you have an audience, maybe even RedBubble or Spring. I started my own shops, not too successful, but I'm trying again. Go for it!

I have a Merch By Amazon store for USA, it is print on demand. Amazing, no over-head :). Once you have a brand, I highly recommend them! But first: - How loyal is your audience? Build an audience first, it is not a thing of building something and the buyers will appear... Unless you're selling in a store as a provider or on Amazon FBA, an audience or sales strategy must come first. - Business model: Could you try making deals with companies who need their logos on merch and need a provider as one business line possibly? - Brand image and purpose: And then, what is the brand about, quality of product, source from Alibaba or is it a premium 100% pima cotton? Or is it about the graphics themselves where it is Print On Demand? - Type: Is it about a certain lifestyle or brand message? Is it to promote a certain style / fashion or is it graphics like anime, who is the artist? What is the driver of the brand? Is it more of a creative project or building a whole brand?

Have you consider print in demand services? These are service that would print your design and ship it to your customers. Whenever your customer place an order you will send these Cos. the order, then they will ship it directly to your customers. Though the profit margin is not that great, but it will help you to taste the water with little to no cost. (check out youtube Vids on Print on demand) You don't need an inventory nor capital. For advertisement you can use instagram influencers or Face book Ad. Hope this will help.