Data is the new gold.
Through events and social media, I have so far collected email addresses through a Qr code on a sheet or a link on social media where people can subscribe to the newsletter.
For example, you post a workshop on social media and then write “if you want to stay informed about future workshops, enter your e-mail address here”
Or at an event “get a chance to win a free skin analysis by scanning the qr code and filling out our form”
The potential new customer then fills in their details themselves and receives email marketing from then on.