Helped Cloudways to reach 89,000 customers with over $52M ARR (recently acquired by DigitalOcean for $350M). Currently, Director, Product Marketing and Content.
I would suggest a few things before going live.
Create a pre-launch page. (Use LaunchRock)
Build your list from ground up. (Start blogging)
Integrate a referral program like Trevolta did. Make them share your voice via social media to get ahead in the list of invitees for the product launch.
Create a pre-launch video.
List your product on Betalist and other similar websites to get beta testers.
List your product on ProductHunt, Hackernews, Reddit etc.
Create a press kit so journalists can find about who your are and what you do to create a story.
Growth Hacking Content Marketing SaaS SaaS - Enterprise & SMB B2B Content Strategy