One high leverage email campaign for Shopify stores is the New Customer Welcome campaign.
Usually its the newer stores that are missing this, though even popular and established stores lack them too.
With a New Customer Welcome campaign you're trying to start off a customer relationship on the right foot. It only targets new customers who just recently made their first purchase.
There's two things you want to focus on with them and one driving principle:
Give them information about their order. This includes shipping estimates, return policies, who to contact for help, etc.
Go into detail about what it's like to own and use your products. Especially if they are complex.
Throughout the campaign you want to keep in mind the principle of building a relationship. Don't go for the quick sale right away, focus on giving good service now and they'll be happier later on (and buy)
If you haven't installed Repeat Customer Insights yet, it's an easy way to get a detailed look at your customer behavior including how new customers compare to repeat customers.
Retain the best customers and leave the worst for your competitors to steal
If you're having problems with customers not coming back or defecting to competitors, Repeat Customer Insights might help uncover why that's happening.
Using its analyses you can figure out how to better target the good customers and let the bad ones go elsewhere.