It may seem counterintuitive, but why not leverage other stores and restaurants that have good customer bases to drive traffic into your store?
Think about it. Pick a nearby store that sells complementary items, and offer their customers a reason to come to your store. If you are a ladies boutique featuring dresses, hats, handbags, etc. then find a well respected and popular ladies shoe store, and offer their customers a 10% discount on their first purchase at your store. Maybe the shoe store will reciprocate and you can do some joint marketing. There is very little work involved in such a partnership, and there's no cost or competitive downside.
You can extend this and even hold workshops or open house days to showcase your products together, helping customers see the link and how well they complement each other. This is a great way to build loyalty and strengthen each brand as well.
Of course, this idea will work in any vertical, not just ladies' accessories. An automotive performance shop could team up with a wheel and tire shop, sharing discounts and driving traffic to one another.
This is a simple technique, but executed properly it can pay big dividends for both parties.