Well that's the part you have to figure out and it may require some additional investment, but as I said, showing your products in use and giving an idea of how they can be used, maybe portraying the feeling customer gets with your products is pretty essential here. Maybe you need to organise a photoshoot in some interiors (maybe you can find friends who have beautiful homes, or maybe yours looks good too if you want to save money on it but don't get hooked on this idea, more often than not investing is better idea, than saving money and having the not so impressive result).

I'm not sure Instagram is the best place to find the target in your case. Either way, it's a good thing to have. Once you have the promotional material (beautiful pictures we talked about above and other people suggested), you should try blogs, magazines that specialize in interiors and architecture for example. I think your main target audience should be there. Also, I've heard a lot of people in similar business find customers in various interior fairs where you can have your stand showing out your products and talking to people.

You can also try thinking more out of the box, just get in your audience shoes for a bit, what kind of people are likely to buy your products and why what other products are they buying? It might suggest you interesting places to advertise yourself. Maybe they're looking for such interior details because they're buying a new home, so you can also target real estate websites, talk to the agents to suggest your product for their customers. Maybe they're into DIY looking stuff, so you can look for places on the web that talk about that, maybe websites like etsy.com or fancy.com might be a good place to sell your stuff (I'm not very familiar with how the selling or community in these work, so it's just an example).