Your customers come to your site in various ways — organically via search engines, ads, social network referrals, or just word of mouth. There are two challenges that you have — how do you get them to buy and how do you get them to come back again.
A lot of our customers spend a lot of money on Google ads only to see those customers not coming back again. This could also mean that your ads are not targeting the right customers. The cost of returning customers is much less than acquiring a new one, and the only way to get the most out of your digital marketing spends is to figure out which strategies are bringing in customers who will return again.
A lot of irrelevant traffic coming to your store could be because you have a vaguely defined target audience. While basic SEO can bring in a lot of traffic, that also means that you are spending a lot of time and money on customers who are not really going to buy from you.
The first step is to build a customer persona, which is nothing but a definition of who your customer is, and what they are looking to buy. This can be accomplished by customer interviews, feedback forms and overall segmentation of your customers, especially the returning ones. Once you know who are returning customers and what their persona is, you can then look at your overall digital marketing strategies and see which ones are targeting those personas and effective as well.
Another way is to look at what your direct competitors are doing, what their strategies are and who their customers are. And if they are effective there is no harm in copying those strategies :).