I took a peek at your shop and I suggest just keep adding more listings. I did not make my first sale until I had nearly 50 listings! the more listings you have the more likely somebody will find your shop, and with your shop having a very specific target customer, you have a high likelihood of them sticking around to scroll thru your entire shop to see what all you have.
my shop is only a few months old but I have found the more listings the better.
you also have a very nice logo, it looks quite professional for a new shop. You could use a service like printify to make stickers / business cards and go to local areas to advertise that way. As long as the service you provide is not something that the business you want to advertise at also provides, they may let you put up a sticker or set a stack of business cards on their counter. Just make sure to add the URL for your shop somewhere on the sticker or business card!
