24 hrs to launch!

I'm finally launching my first saas on the 4th of July. It's the simplest finance tracker and auto budgeting tool that I originally built to address my own budgeting needs, as I couldn't find any suitable tools on the market. Now, I want to share this tool with others. As a complete newbie in marketing, I'd love to get some advice and tips from the community on what I should be doing during this time frame. Any help is greatly appreciated! P.S. I'd also love to hear your stories about your 24 hours before launch!