How did your existing customers found you?

It seems to me that you should work on trying to map your customer journey which is the path the customer takes before they end up buying products similar to yours.

Once you have that mapped out the next step is to figure out how to insert yourself into that process. If they do searches, you need to figure out how to show up for them either through ads or organic and useful content, for example.

Another tip that might be useful is to research your competitor and see how they advertise. Do they make ads? Do they send emails? What wording do they use?

All that should get you started pretty well.