With the winter holidays over, now's the time to start nurturing your new customers.
They're probably burnt out with product offers by now so focus on brand building types of content: how to use their products, other customer's experiences, proactive customer service.
Keep it up during the post-holiday slump and eventually they'll come back and make a second (or third) purchase.
If you want to know when to start sending offers again, check your Customer Purchase Latency in Repeat Customer Insights. That'll tell you how soon on average a customer takes before they make their next purchase.
Timing your offer around then is best.
Analyze your customer behavior
A quick and automatic way to measure your customer behavior is with Repeat Customer Insights. It'll automatically import your Shopify data and run a number of analyses to highlight different customer behavior.