Its going to be a tiring thing, lot of info that you need to learn&gather to keep adding value to your audience, one can't always speak abut their product for every few days, help your audience with good content that helps their business/life then integrate your product into those and demonstrate how your product enhances whole situation.
if there is no value for the reader, its not going to work.
One strategy that's worked for us, Emmanuel, is offering exclusive content or early access to new features for newsletter subscribers, which incentivizes sign-ups. Additionally, leveraging social media platforms with snippets of your newsletter content can pique interest and drive subscriptions.
@fabian_maume about SaaS marketing for builders with advice from known operators and thought leaders who've done it before.
You can read it here: www.earlynode.com
This most important factor for growing a newsletter subscribers is to offer an incentive and invest in content marketing:
for example backlnko.com the leading SEO blog offer newsletter subscribers email only content so they have a value in being a member.
Also backlink.com increased that number by offering posts that are gated only for email subscribers
Another option is offering free stuff like an e-book in exchange for an email newsletter subscription, this done by many sties including @hubpsot
When asking users to join a newsletter showcase how many subscribers you have “like saying join our newsletter to get “something of value” and join 5,000 members. If you are starting with email newsletter and do not have a large number of subscribers do not mention the number until you reach sizable number