How big is your email list? What was your best tip for growing and monetizing it?

I have a couple of email lists for projects - between 200 and 800. Best tip for growing it - write regularly and have a subscribe button in the email itself.

My newsletter "Le Courrier du hacker" is a weekly digest of the activity of the French-speaking FOSS community.

I reached 2k+ subscribers with already 76 issues. Open rate is around 55%. To offer to access the content to people disliking newsletters, I have public archives outside my email provider (Mailchimp) mostly to have a better control of my content. I also have accounts on social networks Twitter and Mastodon…

To grow the audience, I tried to publish relevant content in the french-speaking FOSS community - my readers - in order them to join. I also blog about it on a regular basis. The first 1k subscribers were quite easy to get, now it's more difficult to grow and these days I try partnership with other french newsletters or blogs or websites to exchange visibility.