Makers, how did you convert your first free customers to paying customers?

We’re in the early days of building our customer base. Every week, we have new customers sign up (no credit card required) and try out our product (through a 14-day free trial). Now, we need to figure out the best way to keep our customers engaged and paying once their free-trial is over. I would love to hear from you. What are some methods to ensure free-trial customers convert to paying customers? Here's us on Product Hunt